Equity [Abstract] Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Net unrealized holding (loss) gain on available for sale securities AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member] Net unrealized holding gain (loss) on retirement plans Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Accumulated other comprehensive (loss) AOCI Attributable to Parent [Member] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Available-for-sale securities Available-for-sale Securities [Member] Held-to-maturity securities Held-to-maturity Securities [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Other comprehensive income (loss), before tax Other Comprehensive Income (Loss), before Tax Other comprehensive income (loss), tax benefit Other Comprehensive Income (Loss), Tax Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax Total stockholders’ equity Stockholders' Equity Attributable to Parent Investments, Debt and Equity Securities [Abstract] Securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Debt Instruments [Abstract] Schedule of debt Schedule of Debt [Table Text Block] Summary of securities available for sale Debt Securities, Available-for-sale [Table Text Block] Summary of securities held-to-maturity Debt Securities, Held-to-maturity [Table Text Block] Schedule of held for sale securities transferred to available-for-sale Schedule of New Accounting Pronouncements and Changes in Accounting Principles [Table Text Block] Summary of amortized cost and fair value of investment securities available for sale by remaining period to contractual maturity Investments Classified by Contractual Maturity Date [Table Text Block] Sale of securities Schedule of Realized Gain (Loss) [Table Text Block] Securities available for sale with unrealized losses, by length of time in continuous unrealized loss position Debt Securities, Available-for-sale, Unrealized Loss Position, Fair Value [Table Text Block] Securities pledged for borrowings at FHLB and other institutions, and securities pledged for municipal deposits and other purposes Schedule of Financial Instruments Owned and Pledged as Collateral [Table Text Block] Stockholders' Equity Note [Abstract] Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations Schedule of Compliance with Regulatory Capital Requirements under Banking Regulations [Table Text Block] Retirement Benefits [Abstract] Summary of Company's stock option activity Share-based Payment Arrangement, Option, Activity [Table Text Block] Schedule of stock-based compensation expense associated with stock options and non-vested stock awards Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Unrecognized stock-based compensation expense Share-based Payment Arrangement, Nonvested Award, Cost [Table Text Block] Receivables [Abstract] Allowance for loan losses activity Financing Receivable, Allowance for Credit Loss [Table Text Block] Financing receivable credit quality indicators Financing Receivable Credit Quality Indicators [Table Text Block] Statement of Stockholders' Equity [Abstract] Cash dividends paid, common (usd per share) Common Stock, Dividends, Per Share, Cash Paid Cash dividends paid, preferred (usd per share) Preferred Stock, Dividends, Per Share, Cash Paid Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Retirement Plan Funding Status [Axis] Retirement Plan Funding Status [Axis] Retirement Plan Funding Status [Domain] Retirement Plan Funding Status [Domain] Overfunded Plan Overfunded Plan [Member] Underfunded Plan Underfunded Plan [Member] Retirement Plan Name [Axis] Retirement Plan Name [Axis] Retirement Plan Name [Domain] Retirement Plan Name [Domain] Astoria Bank Pension Plan Astoria Bank Pension Plan [Member] Astoria Bank Pension Plan [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Other assets Other Assets [Member] Other liabilities Other Liabilities [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Net gain due to plan termination Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Curtailment Plan reversion asset recorded upon plan termination Defined Benefit Plan, Amounts for Asset (Liability) Recognized in Statement of Financial Position Employer contributions to fund pension and other post retirement benefits Defined Benefit Plan, Plan Assets, Contributions by Employer Funded (unfunded) amount Defined Benefit Plan, Funded (Unfunded) Status of Plan Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Stock-Based Compensation Share-based Payment Arrangement [Text Block] Schedule of Impaired Financing Receivable [Table] Schedule of Impaired Financing Receivable [Table] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Commercial loans portfolio segment Commercial Portfolio Segment [Member] Residential mortgage portfolio segment Residential Portfolio Segment [Member] Consumer portfolio segment Consumer Portfolio Segment [Member] Industry Sector [Axis] Industry Sector [Axis] Industry Sector [Domain] Industry Sector [Domain] Commercial and industrial Commercial and Industrial Sector [Member] Real estate Real Estate Sector [Member] Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Traditional C&I Commercial And Industrial [Member] A loan, whether secured or unsecured, to a company for purposes such as seasonal working capital needs, inventory financing, equipment purchases and acquisitions. Asset-based lending Asset-Based Lending [Member] Asset-Based Lending [Member] Equipment financing Equipment Financing Receivables [Member] A loan related to equipment finance receivable. CRE Commercial Real Estate [Member] Multi-family Real Estate Loan [Member] Residential mortgage Residential Mortgage [Member] Consumer Consumer Loan [Member] Real Estate, Type of Property [Axis] Real Estate, Type of Property [Axis] Real Estate [Domain] Real Estate [Domain] Multi-family Multifamily [Member] Financing Receivable, Impaired [Line Items] Financing Receivable, Impaired [Line Items] Average recorded investment with no related allowance Impaired Financing Receivable, with No Related Allowance, Average Recorded Investment Interest income recognized with no related allowance Impaired Financing Receivable, with No Related Allowance, Interest Income, Accrual Method Cash-basis interest income recognized with no related allowance Impaired Financing Receivable, with No Related Allowance, Interest Income, Cash Basis Method Derivative Instruments and Hedges, Assets [Abstract] Schedule of Credit Derivatives [Table] Schedule of Credit Derivatives [Table] Derivative Instrument [Axis] Derivative Instrument [Axis] Credit Derivatives Contract Type [Domain] Derivative Contract [Domain] Interest rate swap Interest Rate Swap [Member] Third-party interest rate swap Third Party Interest Rate Swap [Member] Third party interest rate swap. Customer interest rate swap Customer Interest Rate Swap [Member] Customer interest rate swap. Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] One-month LIBOR London Interbank Offered Rate (LIBOR) [Member] Credit Derivatives [Line Items] Credit Derivatives [Line Items] Summary of derivatives Summary of Credit Derivatives [Abstract] Derivative assets, notional amount Derivative Asset, Notional Amount Derivative liabilities, notional amount Derivative Liability, Notional Amount Average maturity (in years) Derivative, Average Remaining Maturity Weighted average fixed rate Derivative, Average Fixed Interest Rate Basis spread Derivative, Basis Spread on Variable Rate Derivative assets, fair value Derivative Asset Swaps Derivative Liability Loans individually evaluated for impairment by segment of loans Loans Individually Evaluated For Impairment By Segment Of Loans [Abstract] Loans individually evaluated for impairment by segment of loans. With no related allowance recorded: Impaired Financing Receivable, Unpaid Principal Balance [Abstract] Unpaid principal balance with no related allowance recorded Impaired Financing Receivable, with No Related Allowance, Unpaid Principal Balance Recorded investment with no related allowance recorded Impaired Financing Receivable, with No Related Allowance, Recorded Investment Number of available for sale securities which were in continuous unrealized loss position for less than 12 months Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Number Of Securities Available for sale securities continuous unrealized loss position less than twelve months number of securities. Number of available for sale securities which were in continuous unrealized loss position for 12 months or more Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Number Of Securities Available for sale securities continuous unrealized loss position twelve months or longer number of securities. Number of held to maturity securities which were in continuous unrealized loss position for less than 12 months Held To Maturity Securities Continuous Loss Position Less Than Twelve Months Number Of Securities Held To Maturity Securities Continuous Loss Position Less Than Twelve Months Number Of Securities Number of held to maturity securities which were in continuous unrealized loss position for 12 months or more Held To Maturity Securities Continuous Loss Position More Than Twelve Months Number Of Securities Held To Maturity Securities Continuous Loss Position More Than Twelve Months Number Of Securities Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] ASU 2017-12 Accounting Standards Update 2017-12 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Book value of available-for-sale securities transfered from held to maturity Debt Securities, Available-for-sale, Amortized Cost Fair value of available-for-sale securities transfered from held to maturity Debt Securities, Available-for-sale Securities sold to raise liquidity Debt Securities, Held-to-maturity, Sold, Amount Cash Paid as STM Derivative, Collateral, Right to Reclaim Cash Financing Receivable, Allowance for Credit Loss [Table] Financing Receivable, Allowance for Credit Loss [Table] Payroll finance Payroll Finance [Member] Payroll Finance [Member] Warehouse lending Warehouse Lending [Member] Warehouse lending [Member] Factored receivables Factored Receivables [Member] A loan related to factored receivables. Public sector finance Public Sector Finance [Member] Public Sector Finance [Member] ADC Acquisition, Development And Construction [Member] Acquisition Development And Construction [Member] Credit Loss Status [Axis] Credit Loss Status [Axis] Credit Loss Status [Domain] Credit Loss Status [Domain] PCI Loans Financial Asset Acquired with Credit Deterioration [Member] Financing Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Loans evaluated for impairment by segment Financing Receivable, Allowance for Credit Loss, Additional Information [Abstract] Loans evaluated by segment, Individually evaluated for impairment Financing Receivable, Individually Evaluated for Impairment Loans evaluated by segment, Collectively evaluated for impairment Financing Receivable, Collectively Evaluated for Impairment Loans evaluated by segment, Purchased credit impaired loans Financing Receivable, after Allowance for Credit Loss Total portfolio loans Loans and Leases Receivable, Gross Allowance evaluated by segment, Individually evaluated for impairment Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment Allowance evaluated by segment, Collectively evaluated for impairment Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment Total allowance for loan losses Financing Receivable, Allowance for Credit Loss Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Stock options Share-based Payment Arrangement, Option [Member] Non-vested stock awards/performance units Non-vested Stock Awards and Performance Units [Member] Non-vested Stock Awards and Performance Units [Member] Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Stock-based compensation expense Share-based Payment Arrangement, Expense Stock-based compensation expense, income tax benefit Share-based Payment Arrangement, Expense, Tax Benefit Proceeds from stock option exercises Proceeds from Stock Options Exercised Unrecognized stock-based compensation, stock options Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Unrecognized stock-based compensation, non-vested stock awards/performance units Share-based Payment Arrangement, Nonvested Award, Excluding Option, Cost Not yet Recognized, Amount Total unrecognized stock-based compensation expense Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Other Income and Expenses [Abstract] Professional fees Professional Fees Advertising and promotion Marketing and Advertising Expense Telephone Communication Operational losses Operational Loss Operational Loss Insurance & surety bond premium Insurance and Surety Bond Premium Expense Insurance and Surety Bond Premium Expense Other Other Noninterest Expense, Miscellaneous Other Noninterest Expense, Miscellaneous Total other non-interest expense Other Noninterest Expense Deposits [Abstract] Deposits Deposit Liabilities Disclosures [Text Block] Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward] Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward] Balance at beginning of period Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Balances acquired in the Woodforest Acquisition Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Additions Accretion of income Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Accretion Charge-offs Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Disposals of Loans Reclassification (to) from non-accretable difference Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Reclassifications (to) from Nonaccretable Difference Other, adjustments Certain Loans Acquired In Transfer Not Accounted For As Debt Securities, Accretable Yield, Other Adjustments Certain Loans Acquired In Transfer Not Accounted For As Debt Securities, Accretable Yield, Other Adjustments Balance at end of period Allowance for Loan Losses Financing Receivables [Text Block] Commercial real estate Commercial Real Estate Portfolio Segment [Member] Multi-family Multi-family financing [Member] Multi-family financing [Member] Summary of activity in allowance for loan losses and recorded investments in loans by portfolio segment based on impairment method Allowance for Loan and Lease Losses [Roll Forward] Beginning allowance for loan losses Loans and Leases Receivable, Allowance Charge-offs Financing Receivable, Allowance for Credit Loss, Writeoff Recoveries Financing Receivable, Allowance for Credit Loss, Recovery Net charge-offs Allowance For Doubtful Accounts Receivable, Charge-Offs (Recoveries), Net Allowance For Doubtful Accounts Receivable, Charge-Offs (Recoveries), Net Provision / (credit) Provision for Loan, Lease, and Other Losses Ending allowance for Loan Losses Annualized net charge-offs to average loans outstanding: Net Charge Offs To Average Gross Loans Annualized Net charge offs to average gross loans annualized. Schedule of Classification of Deposits [Table] Schedule of Classification of Deposits [Table] Schedule of classification of deposits. Brokered Deposits [Axis] Brokered Deposits [Axis] Brokered deposits. Brokered Deposits [Domain] Brokered Deposits [Domain] Brokered Deposits [Domain] Interest bearing demand Interest-bearing Deposits [Member] Money market Money Market Deposits [Member] Money market deposits. Certificates of deposits Certificates of Deposit [Member] Schedule of Classification of Deposits [Line Items] Schedule of Classification of Deposits [Line Items] Schedule of classification of deposits. List of Company's Brokered deposits List of Company's Brokered Deposits [Abstract] List of company's brokered deposits. Brokered deposits Noninterest-bearing Domestic Deposit, Brokered Financial Instruments Owned and Pledged as Collateral [Table] Financial Instruments Owned and Pledged as Collateral [Table] Collateral [Axis] Collateral [Axis] Collateral [Domain] Collateral [Domain] Collateral Pledged Collateral Pledged [Member] Federal Home Loan Bank Borrowings Federal Home Loan Bank Borrowings [Member] Municipal Deposits Municipal Deposits [Member] Municipal deposits. Financial Instruments Owned and Pledged as Collateral [Line Items] Financial Instruments Owned and Pledged as Collateral [Line Items] Available-for-sale, pledged as collateral Debt Securities, Available-for-sale, Restricted Held-to-maturity securities pledged as collateral Debt Securities, Held-to-maturity, Restricted Total securities pledged Restricted Investments Schedule of Other Non-interest Expense Other non- interest expense [Table Text Block] Other non- interest expense [Table Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Remainder of 2019 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year 2020 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2024 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Total Finite-Lived Intangible Assets, Net Income Statement [Abstract] Interest and dividend income: Interest and Dividend Income, Operating [Abstract] Loans and loan fees Interest and Fee Income, Loans and Leases Securities taxable Interest Income, Securities, Operating, Taxable Securities non-taxable Interest Income, Securities, Operating, Tax Exempt Other earning assets Other Interest and Dividend Income Total interest and dividend income Interest and Dividend Income, Operating Interest expense: Interest Expense [Abstract] Deposits Interest Expense, Deposits Borrowings Interest Expense, Borrowings Total interest expense Interest Expense Net interest income Interest Income (Expense), Net Provisions for loan losses Provision for Loan and Lease Losses Net interest income after provision for loan losses Interest Income (Expense), after Provision for Loan Loss Non-interest income: Noninterest Income [Abstract] Deposit fees and service charges Revenue from Contract with Customer, Including Assessed Tax Accounts receivable management / factoring commissions and other fees Accounts Receivable Management Fees, Factoring Commissions And Other Related Fees Accounts receivable / factoring commissions and other related fees Bank owned life insurance Bank Owned Life Insurance Income Loan commissions and fees Fees And Commissions, Loans Fees And Commissions, Loans Investment management fees Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions Net gain (loss) on sale of securities Debt and Equity Securities, Gain (Loss) Gain on termination of pension plan Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement Gain on sale of fixed assets Gain (Loss) on Disposition of Property Plant Equipment Gain on sale of residential mortgage loans Gain (Loss) on Sale of Mortgage Loans Other Noninterest Income, Other Total non-interest income Noninterest Income Non-interest expense: Noninterest Expense [Abstract] Compensation and benefits Labor and Related Expense Stock-based compensation plans Employee Stock Ownership Plan (ESOP) And Stock Based Compensation Expense Employee Stock Ownership Plan (ESOP) And Stock Based Compensation Expense Occupancy and office operations Occupancy, Net Information technology Information Technology and Data Processing Amortization of intangible assets Amortization of Intangible Assets FDIC insurance and regulatory assessments Federal Deposit Insurance Corporation Premium Expense Other real estate owned expense, net Other Real Estate Owned, Income (Expense), Net Other Real Estate Owned, Income (Expense), Net Charge for asset write-downs, retention and severance Asset Impairment, Severance, And Retention Charges Asset Impairment, Severance, And Retention Charges Impairment related to financial centers and real estate consolidation strategy Asset Impairment Charges Other Total non-interest expense Noninterest Expense Income before income tax expense Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Income tax expense Income Tax Expense (Benefit) Net income Net Income (Loss) Attributable to Parent Preferred stock dividend Preferred Stock Dividends and Other Adjustments Net income available to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Weighted average common shares: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Earnings per common share: Earnings Per Share [Abstract] Basic (USD per share) Earnings Per Share, Basic Diluted (USD per share) Earnings Per Share, Diluted Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Debt Securities, Held-to-maturity [Table] Debt Securities, Held-to-maturity [Table] Agency-backed Agency Securities [Member] CMOs/Other MBS Collateralized Mortgage Obligations [Member] Total residential MBS Residential Mortgage Backed Securities [Member] Federal agencies US Government Agencies Debt Securities [Member] Corporate Corporate Debt Securities [Member] State and municipal US States and Political Subdivisions Debt Securities [Member] Other Other Investment Securities [Member] Other investment securities. Total other securities Securities Investment [Member] Schedule of Held-to-maturity Securities [Line Items] Schedule of Held-to-maturity Securities [Line Items] Fair value, less than 12 months Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Fair Value Unrecognized losses, less than 12 months Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Fair value, 12 months or longer Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Fair Value Unrecognized losses, 12 months or longer Debt Securities, Held-to-maturity, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Fair value, total Debt Securities, Held-to-maturity, Unrealized Loss Position, Fair Value Unrecognized losses, total Debt Securities, Held-to-maturity, Unrealized Loss Position, Accumulated Loss Borrowings Debt Disclosure [Text Block] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Date [Axis] Award Date [Axis] Award Date [Domain] Award Date [Domain] February 2016 February 2016 [Member] February 2016 [Member] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] Recognition and Retention Plan Recognition and Retention Plan [Member] Recognition and Retention Plan [Member] Amended Omnibus Plan Amended And Restated 2015 Omnibus Plan [Member] Amended And Restated 2015 Omnibus Plan [Member] Performance Shares Performance Shares [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant [Roll Forward] Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant [Roll Forward] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Amended 2015 Omnibus Equity and Incentive Plan Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Granted (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Granted In Period Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Granted In Period Stock awards vested (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Vested In Period Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Vested In Period Exercised (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Exercised In Period Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Exercised In Period Forfeited (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Forfeitures in Period Share-Based Compensation Arrangement By Share-Based Payment Award, Forfeitures in Period Canceled/expired (in shares) Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Cancellations in Period Share-Based Compensation Arrangement By Share-Based Payment Award, Shares Available For Grant, Cancellations in Period Ending balance (in shares) Non-vested stock awards/stock units outstanding - Number of shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Stock awards vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Canceled/expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Expirations Ending balance (in shares) Non-vested stock awards/stock units outstanding - Weighted average grant date fair value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Beginning balance (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Stock awards vested (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Forfeited (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Canceled/expired (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expirations, Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expirations, Weighted Average Grant Date Fair Value Ending balance (USD per share) Stock options outstanding - Number of shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Stock awards vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Canceled/expired (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Expirations in Period Ending balance (in shares) Exercisable at end of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Stock options outstanding - Weighted average exercise price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Beginning balance (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Stock awards vested (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value Exercised (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Forfeited (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Canceled/expired (USD per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Expirations in Period, Weighted Average Exercise Price Ending balance (USD per share) Exercisable at end of period (USD per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Performance measurement period Share-based Compensation Arrangement by Share-based Payment Award, Award Performance Measurement Period Share-based Compensation Arrangement by Share-based Payment Award, Award Performance Measurement Period Vesting percentage Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Statement of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net income Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Net (gain) from write-downs and sales of other real estate owned Gains (Losses) on Sales of Other Real Estate Net (gain) on extinguishment of Senior Notes Gain (Loss) on Extinguishment of Debt Depreciation of premises and equipment Depreciation, Depletion and Amortization Impairment on fixed assets Impairment of Long-Lived Assets Held-for-use Impairment of early termination of leases Gain (Loss) on Termination of Lease Asset write-downs, retention and severance compensation and other restructuring charges Restructuring Costs and Asset Impairment Charges Income from termination of defined benefit pension plan Gain (Loss) on Contract Termination Amortization of intangible assets Amortization of low income housing tax credits Amortization Method Qualified Affordable Housing Project Investments, Amortization Net loss on sale of securities Net gain on loans held for sale Gain (Loss) on Sales of Loans, Net Net gain on sale of premises and equipment Net amortization of premiums on securities Accretion (Amortization) of Discounts and Premiums, Investments Amortization of premium on certificates of deposit Accretion (Amortization) Of Discounts And Premiums, Certificates Of Deposit Accretion (Amortization) Of Discounts And Premiums, Certificates Of Deposit Net accretion of purchase discount and amortization of net deferred loan costs Accretion (Amortization) of Discounts and Premiums, Loans Accretion (Amortization) of Discounts and Premiums, Loans Net accretion of debt issuance costs and amortization of premium on borrowings Amortization of Debt Discount (Premium) Restricted stock compensation expense Restricted Stock or Unit Expense Stock option compensation expense Stock or Unit Option Plan Expense Originations of loans held for sale Payments for Origination and Purchases of Loans Held-for-sale Proceeds from sales of loans held for sale Proceeds from Sale of Loans Held-for-sale Increase in cash surrender value of bank owned life insurance Life Insurance, Corporate or Bank Owned, Change in Value Deferred income tax expense Increase (Decrease) in Deferred Income Taxes Other adjustments (principally net changes in other assets and other liabilities) Other Operating Activities, Cash Flow Statement Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Purchases of securities: Payments to Acquire Investments [Abstract] Available for sale Payments to Acquire Debt Securities, Available-for-sale Held to maturity Payments to Acquire Held-to-maturity Securities Proceeds from maturities, calls and other principal payments on securities: Proceeds from Sale, Maturity and Collection of Investments [Abstract] Available for sale Proceeds from Maturities, Prepayments and Calls of Debt Securities, Available-for-sale Held to maturity Proceeds from Maturities, Prepayments and Calls of Held-to-maturity Securities Proceeds from sales of securities available for sale Proceeds from Sale of Debt Securities, Available-for-sale Proceeds from sales of securities held to maturity Proceeds from Sale of Held-to-maturity Securities Portfolio loan originations, net Payments for Loan originations Cash outflows for the origination of new loans during the period. Portfolio loans purchased Payments to Acquire Loans Receivable Proceeds from sale of residential mortgage loans Proceeds from Sale of Loans Held-for-investment Redemptions (purchases) of FHLB and FRB stock, net Payments for (Proceeds from) Federal Home Loan Bank Stock Proceeds from sales of other real estate owned Proceeds from Sale of Other Real Estate Purchases of premises and equipment Payments to Acquire Property, Plant, and Equipment Proceeds from bank owned life insurance Proceeds from Life Insurance Policy Proceeds from sale of premises and equipment Proceeds from Sale of Property, Plant, and Equipment Purchases of low income housing tax credits Payments to Acquire Affordable Housing Tax Credit Payments to Acquire Affordable Housing Tax Credit Cash paid for acquisition, net Payments for (Proceeds from) Businesses and Interest in Affiliates Net cash provided by (used in) investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Net (decrease) increase in transaction, savings and money market deposits Net Change Interest and Noninterest-bearing Deposits, Domestic Net increase in certificates of deposit Increase (Decrease) in Time Deposits Net (decrease) in short-term FHLB borrowings Payments Of Short Term FHLBank Borrowings, Financing Activities Payments Of Short Term FHLBank Borrowings, Financing Activities Advances of term FHLB borrowings Proceeds from FHLBank Borrowings, Financing Activities Repayments of term FHLB borrowings Payments of FHLBank Borrowings, Financing Activities Repayment of Senior Notes Repayments of Senior Debt Net increase (decrease) in other borrowings Proceeds from (Repayments of) Other Debt Net increase (decrease) in mortgage escrow funds Payments for (Proceeds from) Deposit on Loan Treasury shares repurchased Payments for Repurchase of Common Stock Cash dividends paid - common stock Payments of Ordinary Dividends Cash dividends paid - preferred stock Payments of Ordinary Dividends, Preferred Stock and Preference Stock Net cash (used in) provided by financing activities Net Cash Provided by (Used in) Financing Activities Net decrease in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash and cash equivalents at beginning of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash and cash equivalents at end of period Supplemental cash flow information: Supplemental Cash Flow Information [Abstract] Interest payments Interest Paid, Excluding Capitalized Interest, Operating Activities Income tax payments Income Taxes Paid Real estate acquired in settlement of loans Real Estate Owned, Transfer to Real Estate Owned Residential mortgage loans transferred from held for sale to portfolio Transfer of Loans Held-for-sale to Portfolio Loans Securities held to maturity transferred to available for sale Securities held to maturity transferred to available for sale Securities held to maturity transferred to available for sale Operating cash flows from operating leases Operating Lease, Payments Right-of-use assets obtained in exchange for lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Acquisitions: Noncash or Part Noncash Acquisition, Net Nonmonetary Assets Acquired (Liabilities Assumed) [Abstract] Non-cash assets acquired: Noncash or Part Noncash Acquisition, Value of Assets Acquired [Abstract] Total loans, net Noncash or Part Noncash Acquisition, Loans and Leases Receivable Acquired Noncash or Part Noncash Acquisition, Loans and Leases Receivable Acquired Accrued interest receivable Noncash or Part Noncash Acquisition, Interest Receivable Acquired Noncash or Part Noncash Acquisition, Interest Receivable Acquired Goodwill Noncash or Part Noncash Acquisition, Goodwill Acquired Noncash or Part Noncash Acquisition, Goodwill Acquired Premises and equipment, net Noncash or Part Noncash Acquisition, Fixed Assets Acquired Other assets Noncash or Part Noncash Acquisition, Other Assets Acquired Total non-cash assets acquired Noncash or Part Noncash Acquisition, Value of Assets Acquired Liabilities assumed: Noncash or Part Noncash Acquisition, Value of Liabilities Assumed [Abstract] Other liabilities Noncash or Part Noncash Acquisition, Other Liabilities Assumed Total liabilities assumed Noncash or Part Noncash Acquisition, Value of Liabilities Assumed Net non-cash assets acquired Noncash or Part Noncash Acquisition, Net Nonmonetary Assets Acquired (Liabilities Assumed) Cash and cash equivalents received in acquisitions Cash Acquired from Acquisition Total consideration paid Business Combination, Consideration Transferred Summary of derivatives Schedule of Derivative Instruments [Table Text Block] Estimated fair value on a recurring basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Impaired loans measured at estimated fair value on nonrecurring basis Fair Value Measurements, Nonrecurring [Table Text Block] Carrying amounts and estimated fair value of financial assets and liabilities Fair Value, by Balance Sheet Grouping [Table Text Block] Income Tax Disclosure [Abstract] Efftective tax rate reconciliation: Effective Income Tax Rate Reconciliation, Percent [Abstract] Income before income tax expense Tax at federal statutory rate of 21% Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount State and local income taxes, net of federal tax benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Tax exempt interest, net of disallowed interest Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount BOLI income Income Tax Reconciliation, Bank Owned Life Insurance Income Income Tax Reconciliation, Bank Owned Life Insurance Income Low income housing tax credits and other benefits Effective Income Tax Rate Reconciliation, Tax Credit, Low Income Housing, Amount Effective Income Tax Rate Reconciliation, Tax Credit, Low Income Housing, Amount Low income housing investment amortization expense Effective Income Tax Rate Reconciliation, Tax Credit, Low Income Housing Amortization Expense, Amount Effective Income Tax Rate Reconciliation, Tax Credit, Low Income Housing Amortization Expense, Amount Equity-based stock compensation benefit Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount FDIC insurance premium limitation Effective Income Tax Rate Reconciliation, FDIC Insurance Premium Limitation Effective Income Tax Rate Reconciliation, FDIC Insurance Premium Limitation Other, net Effective Income Tax Rate Reconciliation, Other Adjustments, Amount Actual income tax expense Effective income tax rate Effective Income Tax Rate Reconciliation, Percent Net deferred tax liability Deferred Tax Liabilities, Net Net deferred tax asset Deferred Tax Assets, Net Valuation allowance Deferred Tax Assets, Valuation Allowance Unrecognized tax benefits Unrecognized Tax Benefits Financing Receivable, Troubled Debt Restructuring [Table] Financing Receivable, Troubled Debt Restructuring [Table] Financial Asset, Other than Financial Asset Acquired with Credit Deterioration Financial Asset, Other than Financial Asset Acquired with Credit Deterioration [Member] Financial Asset, Period Past Due [Axis] Financial Asset, Period Past Due [Axis] Financial Asset, Period Past Due [Domain] Financial Asset, Period Past Due [Domain] 30-59 days past due Financial Asset, 30 to 59 Days Past Due [Member] 60-89 days past due Financial Asset, 60 to 89 Days Past Due [Member] 90 days past due Financial Asset, Equal to or Greater than 90 Days Past Due [Member] Financing Receivable, Troubled Debt Restructuring [Line Items] Financing Receivable, Troubled Debt Restructuring [Line Items] Current loans Trouble Debt restructuring current loans Trouble Debt restructuring current loans Past due TDRs Financing Receivable, Troubled Debt Restructuring Non- accrual Non Accrual Loans Under Troubled debt restructurings Non accrual loans. Commitments and Contingencies Disclosure [Abstract] Schedule of Fair Value, Off-balance Sheet Risks [Table] Schedule of Fair Value, Off-balance Sheet Risks [Table] Loan origination commitments Loan Origination Commitments [Member] Unused lines of credit Unused lines of Credit [Member] Letters of credit Letter of Credit [Member] Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items] Lending-related instruments Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Receivables without deteriorated credit quality Receivables Without Deteriorated Credit Quality [Member] Receivables Without Deteriorated Credit Quality [Member] Receivables acquired with deteriorated credit quality Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Recorded investment non-accrual loans Financing Receivable, Nonaccrual Non-accrual loans, unpaid principal balance Financing Receivable, Recorded Investment, Nonaccrual Status, Unpaid Principal Balance Financing Receivable, Recorded Investment, Nonaccrual Status, Unpaid Principal Balance Accumulated Other Comprehensive Income (Loss) Comprehensive Income (Loss) Note [Text Block] Subsequent Events [Abstract] Subsequent Event [Table] Subsequent Event [Table] Receivable Type [Axis] Receivable Type [Axis] Receivable [Domain] Receivable [Domain] Originated Loan Originated Loan [Member] Originated Loan [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Santander Bank, N.A Santander Bank, N.A [Member] Santander Bank, N.A [Member] Subsequent Event [Line Items] Subsequent Event [Line Items] Portfolio loans Tax-equivalent yield Loans and Leases Receivable, Tax-Equivalent Yield Loans and Leases Receivable, Tax-Equivalent Yield Approximate duration Loans And Leases Receivable, Duration Loans And Leases Receivable, Duration Average relationship size Loans And Leases Receivable, Average Size Of Loan Or Lease Loans And Leases Receivable, Average Size Of Loan Or Lease Leases [Abstract] Leases Lessee, Operating Leases [Text Block] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] CMOs/Other MBS Book value of held to maturity securities transfered to available-for-sale Debt Securities, Held-to-maturity Fair value of held to maturity securities transfered to available-for-sale Debt Securities, Held-to-maturity, Fair Value Statement [Table] Statement [Table] Common stock Common Stock [Member] Preferred stock Preferred Stock [Member] Additional paid-in capital Additional Paid-in Capital [Member] Treasury stock Treasury Stock [Member] Retained earnings Retained Earnings [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Balance (in shares) Shares, Issued Balance, beginning Other comprehensive income (loss) Stock options & other stock transactions, net (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Period Increase (Decrease) Stock options & other stock transactions, net APIC, Share-based Payment Arrangement, Recognition and Exercise Restricted stock awards, net (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Restricted stock awards, net Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Cash dividends declared, common Dividends, Common Stock, Cash Cash dividends declared, preferred Dividends, Preferred Stock, Cash Purchase of treasury stock (in shares) Treasury Stock, Shares, Acquired Purchase of treasury stock Treasury Stock, Value, Acquired, Cost Method Reclassification of the stranded income tax effects from the enactment of the Tax Cuts and Jobs Act from accumulated other comprehensive (loss) Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect Balance (in shares) Balance, ending Subsequent Event - Acquisition of Commercial Equipment Finance Loans and Leases Subsequent Events [Text Block] Acquired Loan Acquired Loan [Member] Acquired Loan [Member] Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] Special mention Special Mention [Member] Substandard Substandard [Member] Factored receivables Gross loans by segment Derivatives Derivative Instruments and Hedging Activities Disclosure [Text Block] Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Internal Credit Assessment [Axis] Nonperforming loans Nonperforming Financial Instruments [Member] Financing Receivable, Past Due [Line Items] Financing Receivable, Past Due [Line Items] Non-Performing loans: Non Performing Loans [Abstract] Non performing loans. Current loans Financing Receivable, Not Past Due Past due loans Financing Receivable, Past Due Non accrual loans Non-Accrual TDRs Non-performing loans: Non Performing Assets [Abstract] Non performing assets: Loans 90 days past due and still accruing Financing Receivable, 90 Days or More Past Due, Still Accruing Total non-performing loans Non Performing Loans Total Total non performing loans. Municipal deposits Municipal Deposits Municipal deposits. Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Cover page. Document Information [Table] Document Information [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Common Stock, Par Value $0.01 Per Share Common Stock, Par Value $0.01 Per Share [Member] Common Stock, Par Value $0.01 Per Share [Member] Depositary Shares, Each Representing 1/40th Interest In A Share Of 6.50% Non-Cumulative Perpetual Preferred Stock, Series A Depositary Shares, Each Representing 1/40th Interest In A Share Of 6.50% Non-Cumulative Perpetual Preferred Stock, Series A [Member] Depositary Shares, Each Representing 1/40th Interest In A Share Of 6.50% Non-Cumulative Perpetual Preferred Stock, Series A [Member] Document Information [Line Items] Document Information [Line Items] Document Type Document Type Document Quarterly Report Document Quarterly Report Document Transition Report Document Transition Report Document Period End Date Document Period End Date Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Smaller Reporting Company Entity Small Business Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding (in shares) Entity Common Stock, Shares Outstanding Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Available for sale: Debt Securities, Available-for-sale [Abstract] Amortized cost Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract] Available-for-sale, one year or less, amortized cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost Available-for-sale, one to five years, amortized cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost Available-for-sale, five to ten years, amortized cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost Available-for-sale, greater than ten years, amortized cost Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost Available-for-sale, with a stated maturity date, amortized cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost Available-for-sale, without single maturity date, amortized cost Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Amortized Cost Amortized cost Fair value Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract] Available-for-sale, one year or less, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Available-for-sale, one to five years, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value Available-for-sale, five to ten years, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value Available-for-sale, greater than ten years, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value Available-for-sale, with a stated maturity date, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value Available-for-sale, without single maturity date, fair value Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value Securities available for sale Held to Maturity Debt Securities, Held-to-maturity [Abstract] Amortized cost Debt Securities, Held-to-maturity, Maturity, Amortized Cost, Net [Abstract] Held-to-maturity, one year or less, amortized cost Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost Held-to-maturity, one to five years, amortized cost Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost Held-to-maturity, five to ten years, amortized cost Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost Held-to-maturity, greater than ten years, amortized cost Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Amortized Cost Held-to-maturity, with a stated maturity date, amortized cost Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Amortized Cost Held-to-maturity, without single maturity date, amortized cost Debt Securities, Held-to-maturity, Maturity, without Single Maturity Date, Amortized Cost Amortized cost Fair value Debt Securities, Held-to-maturity, Maturity, Fair Value [Abstract] Held-to-maturity, one year or less, fair value Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Held-to-maturity, one to five years, fair value Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value Held-to-maturity, five to ten years, fair value Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value Held-to-maturity, greater than ten years, fair value Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value Held-to-maturity, with a stated maturity date, fair value Debt Securities, Held-to-maturity, Maturity, Allocated and Single Maturity Date, Fair Value Held-to-maturity, without single maturity date, fair value Debt Securities, Held-to-maturity, Maturity, without Single Maturity Date, Fair Value Held-to-maturity, fair value Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Estimate of Fair Value Measurement Estimate of Fair Value Measurement [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Woodforest National Bank Woodforest National Bank [Member] Woodforest National Bank [Member] Advantage Funding Advantage Funding Management Co., Inc. [Member] Advantage Funding Management Co., Inc. [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Consideration paid Payments to Acquire Businesses, Gross Outstanding loans and leases held by acquiree at acquisition date Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Assets Premium paid for loans receivable, percentage of gross loans Business Combination, Premium Paid For Loans Receivable, Percent Of Gross Loans Business Combination, Premium Paid For Loans Receivable, Percent Of Gross Loans Unpaid principal balance of loans acquired Loans And Leases Receivable, Unpaid Principal Balance Loans And Leases Receivable, Unpaid Principal Balance Restructuring and integration costs Business Combination, Integration Related Costs Percentage of interest acquired Business Acquisition, Percentage of Voting Interests Acquired Loan premium Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Loan Premium Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets, Loan Premium Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Lessee, Lease, Description [Line Items] Lessee, Lease, Description [Line Items] Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Operating lease liabilities Operating Lease, Liability Operating lease remaining lease term Operating Lease, Remaining Lease Term Operating Lease, Remaining Lease Term Operating lease renewal term Lessee, Operating Lease, Renewal Term Operating lease option to terminate term Lessee, Operating Lease, Option To Terminate Term Lessee, Operating Lease, Option To Terminate Term Operating leases rent expense, before Topic 842 adoption Operating Leases, Rent Expense, Net Income Taxes Income Tax Disclosure [Text Block] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Fair Value, Measurements, Nonrecurring Fair Value, Nonrecurring [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Level 1 inputs Fair Value, Inputs, Level 1 [Member] Level 2 inputs Fair Value, Inputs, Level 2 [Member] Level 3 inputs Fair Value, Inputs, Level 3 [Member] Types of Financial Instruments [Domain] Traditional C&I Multi-family Real Estate Commercial Mortgage CBL [Member] Real estate commercial mortgage CBL. Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Total impaired loans measured at fair value Loans Receivable, Fair Value Disclosure Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Carrying amount Reported Value Measurement [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Financial assets: Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Cash and cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Available for sale, at fair value Securities held to maturity, fair value Loans held for sale Loans Held-for-sale, Fair Value Disclosure Portfolio loans, net Accrued interest receivable on securities Accrued Interest Receivables, Securities, Fair Value Disclosure Accrued interest receivables fair value disclosure. Accrued interest receivable on loans Accrued Interest Receivables, Loans, Fair Value Disclosure Accrued Interest Receivables, Loans, Fair Value Disclosure FHLB stock and FRB stock Investment in Federal Home Loan Bank Stock, Fair Value Disclosure Swaps Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] Non-maturity deposits Non Maturity Deposits Fair Value Disclosure Non maturity deposits fair value disclosure. Certificates of deposit Certificates Of Deposit Fair Value Disclosure Certificates of deposit fair value disclosure. FHLB borrowings Federal Home Loan Bank Borrowings, Fair Value Disclosure Other borrowings Other Borrowings Senior Notes Senior Notes Subordinated Notes Subordinated Debt Mortgage escrow funds Mortgage Escrow Funds Fair Value Disclosure Mortgage escrow funds fair value disclosure. Accrued interest payable on deposits Accrued Interest Payable, Deposits Including Escrow, Fair Value Disclosure Accrued Interest Payable, Deposits Including Escrow, Fair Value Disclosure Accrued interest payable on borrowings Accrued Interest Payable, Borrowings, Fair Value Disclosure Accrued Interest Payable, Borrowings, Fair Value Disclosure Schedule of Lease Cost Lease, Cost [Table Text Block] Schedule of Operating Lease Liability Maturities Lessee, Operating Lease, Liability, Maturity [Table Text Block] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Available for Sale Gross unrealized gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Gross unrealized losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Gross unrecognized gains Debt Securities, Held-to-maturity, Accumulated Unrecognized Gain Gross unrecognized losses Debt Securities, Held-to-maturity, Accumulated Unrecognized Loss Acquisitions Business Combination Disclosure [Text Block] Statement of Financial Position [Abstract] ASSETS: Assets [Abstract] Cash and due from banks Cash and Due from Banks Securities: Marketable Securities [Abstract] Held to maturity, at amortized cost (fair value of $2,061,887 and $2,740,522 at September 30, 2019 and December 31, 2018, respectively) Total securities Investments Loans held for sale Loans Receivable Held-for-sale, Net, Not Part of Disposal Group Allowance for loan losses Portfolio loans, net Loans and Leases Receivable, Net Amount Federal Home Loan Bank (“FHLB”) and Federal Reserve Bank (“FRB”) stock, at cost Federal Home Loan Bank Stock Accrued interest receivable Interest Receivable Premises and equipment, net Property, Plant and Equipment, Net Goodwill Goodwill Other intangible assets, net Intangible Assets, Net (Excluding Goodwill) Bank owned life insurance (“BOLI”) Bank Owned Life Insurance Other real estate owned Other Real Estate, Foreclosed Assets, and Repossessed Assets Other assets Other Assets Total assets Assets LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] LIABILITIES: Liabilities [Abstract] Deposits Deposits FHLB borrowings Long-term Federal Home Loan Bank Advances Repurchase agreements Securities Sold under Agreements to Repurchase Senior Notes Subordinated Notes Mortgage escrow funds Advance Payments by Borrowers for Taxes and Insurance Other liabilities Other Liabilities Total liabilities Liabilities Commitments and Contingent liabilities (See Note 17. “Commitments and Contingencies”) Commitments and Contingencies STOCKHOLDERS’ EQUITY: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock (par value $0.01 per share; 10,000,000 shares authorized; 135,000 shares issued and outstanding at September 30, 2019 and December 31, 2018) Preferred Stock, Value, Issued Common stock (par value $0.01 per share; 310,000,000 shares authorized at September 30, 2019 and December 31, 2018; 229,872,925 shares issued at September 30, 2019 and December 31, 2018; 202,392,884 and 216,227,852 shares outstanding at September 30, 2019 and December 31, 2018, respectively) Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Treasury stock, at cost (27,480,041 shares at September 30, 2019 and 13,645,073 shares at December 31, 2018) Treasury Stock, Value Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income (loss), net of tax expense (benefit) of $17,239 at September 30, 2019 and $(25,429) at December 31, 2018 Accumulated Other Comprehensive Income (Loss), Net of Tax Total stockholders’ equity Total liabilities and stockholders’ equity Liabilities and Equity Net income available to common stockholders Weighted average common shares outstanding for computation of basic EPS (in shares) Common-equivalent shares due to the dilutive effect of stock options and unvested performance share grants (in shares) Weighted Average Number Diluted Shares Outstanding Adjustment Weighted average common shares for computation of diluted EPS (in shares) EPS(2): Earnings Per Share, Basic and Diluted [Abstract] Weighted average common shares that could be exercised that were anti-dilutive for the period (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] FHLB borrowings Federal Home Loan Bank Advances [Member] Repurchase agreements Federal Funds Purchased and Securities Sold under Agreements to Repurchase [Member] Senior Notes Senior Notes [Member] Subordinated Notes Subordinated Debt [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 3.50% Senior Notes Senior Notes, 3.50% [Member] Senior Notes, 3.50% [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Interest rate Debt Instrument, Interest Rate, Stated Percentage Schedule of debt Long-term Debt, by Category, Current and Noncurrent [Abstract] By period to maturity: Long-term Debt, Rolling Maturity [Abstract] Total borrowings, amount Long-term Debt Total borrowings, rate Long-term Debt, Weighted Average Interest Rate, at Point in Time Less than one year, amount Long-term Debt, Maturities, Repayments of Principal in Next Rolling Twelve Months Less than one year, rate Long Term Debt Maturities Weighted Average Interest Rate In Next Rolling Twelve Months Long term debt maturities weighted average interest rate in next rolling twelve months. One to two years, amount Long-term Debt, Maturities, Repayments of Principal in Rolling Year Two One to two years, rate Long Term Debt Maturities Weighted Average Interest Rate In Rolling Year Two Long term debt maturities weighted average interest rate in rolling year two. Two to three years, amount Long-term Debt, Maturities, Repayments of Principal in Rolling Year Three Two to three years, rate Long Term Debt Maturities Weighted Average Interest Rate In Rolling Year Three Long term debt maturities weighted average interest rate in rolling year three. Greater than five years, amount Long-term Debt, Maturities, Repayments of Principal in Rolling after Year Five Greater than five years, rate Long Term Debt Maturities Weighted Average Interest Rate In Rolling After Year Five Long term debt maturities weighted average interest rate in rolling after year five. Organization, Consolidation and Presentation of Financial Statements [Abstract] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Adoption of New Accounting Standards and Recently Issued Accounting Standards Not Yet Adopted New Accounting Pronouncements, Policy [Policy Text Block] Fair Value Measurement, Policy Fair Value Measurement, Policy [Policy Text Block] Measurement Input Type [Axis] Measurement Input Type [Axis] Measurement Input Type [Domain] Measurement Input Type [Domain] Measurement Input, Prepayment Rate Measurement Input, Prepayment Rate [Member] Measurement Input, Discount Rate Measurement Input, Discount Rate [Member] Weighted Average Weighted Average [Member] Changes in fair value recognized on provisions on loans held by the Company Changes In Fair Value Recognized On Provisions On Loans Held By Company Changes in fair value recognized on provisions on loans held by company. Servicing assets and liabilities, measurement input Servicing Assets and Servicing Liabilities at Fair Value, Assumptions Used to Estimate Fair Value, Discount Rate Mortgage servicing rights Servicing Asset at Fair Value, Amount Percentage appraisals discounted Other Real Estate, Appraisal, Discount Rate Other Real Estate, Appraisal, Discount Rate Assets taken in foreclosure, defaulted loans and facilities held for sale Changes in fair value recognized through income for foreclosed assets held by the Company Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss Included In Income Fair Value Assets Measured On Recurring Basis Change In Unrealized Gain Loss Included In Income Remainder of 2019 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2020 Lessee, Operating Lease, Liability, Payments, Due Year Two 2021 Lessee, Operating Lease, Liability, Payments, Due Year Three 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four 2023 Lessee, Operating Lease, Liability, Payments, Due Year Five 2024 Lessee, Operating Lease, Liability, Payments, Due Year Six Lessee, Operating Lease, Liability, Payments, Due Year Six 2025 and thereafter Lessee, Operating Lease, Liability, Payments, Due After Year Six Lessee, Operating Lease, Liability, Payments, Due After Year Six Total lease payments Lessee, Operating Lease, Liability, Payments, Due Interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Present value of lease liabilities Accounting Policies [Abstract] Non-interest bearing demand Demand Deposit Accounts Interest bearing demand Deposits, Negotiable Order of Withdrawal (NOW)