Document And Entity Information [Abstract] Document and entity information. Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Current Reporting Status Entity Current Reporting Status Entity Voluntary Filers Entity Voluntary Filers Entity Filer Category Entity Filer Category Entity Shell Company Entity Shell Company Entity Shell Company Entity Small Business Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Emerging Growth Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Public Float Entity Public Float Earnings Per Share [Abstract] Numerator: Income Loss From Operation Before Extraordinary Items Per Basic And Diluted Share [Abstract] Income loss from operation before extraordinary items per basic and diluted share. Net income (loss) attributable to controlling stockholders and participating securities Net Income (Loss) Attributable to Parent Less: Dividends paid on participating securities Dividend Paid On Participating Securities Dividend Paid On Participating Securities Undistributed earnings attributable to participating securities Undistributed Earnings To Participating Securities Undistributed Earnings To Participating Securities Net income (loss) attributable to controlling stockholders Net Income Loss Available To Common Stockholders Basic And Diluted Net Income Loss Available To Common Stockholders Basic And Diluted Denominator: Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract] Weighted-average number of common shares-basic (in shares) Weighted Average Number of Shares Outstanding, Basic Weighted-average number of common shares-diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Basic earnings per common share (in usd per share) Earnings Per Share, Basic Diluted earnings per common share (in usd per share) Earnings Per Share, Diluted Other Information: Earnings Per Unit [Abstract] Weighted-average number of OP units (in shares) Weighted Average Number of Operating Partnership Units Weighted average number of operating partnership units. Unvested restricted common stock outstanding (i.e. participating securities) (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Quarterly Financial Information Disclosure [Abstract] Selected Quarterly Financial Data (Unaudited) Quarterly Financial Information [Text Block] Debt Disclosure [Abstract] 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] Convertible Notes Payable [Member] Convertible Notes Payable [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 4.125% Convertible Senior Notes Due September 1, 2022 [Member] Four Point One Two Five Percentage Convertible Senior Notes Due September One Two Thousand Twenty Two [Member] 4.125% convertible senior notes due september 1, 2022. Debt Instrument [Line Items] Debt Instrument [Line Items] Principal Debt Instrument, Face Amount Principal, net of issuance costs Long-term Debt Interest rate Debt Instrument, Interest Rate, Stated Percentage Conversion rate of shares for each $1,000 principal amount of convertible notes Debt Instrument, Convertible, Conversion Ratio Conversion of debt equals shares (in shares) Debt Conversion, Converted Instrument, Shares Issued Conversion price per share (in usd per share) Debt Instrument, Convertible, Conversion Price Adjustment for dividends declared (in usd per share) Adjustment For Dividends Declared Minimum Adjustment for dividends declared minimum. Redemption price, percentage Debt Instrument, Redemption Price, Percentage Summary of Quarterly Financial Data Quarterly Financial Information [Table Text Block] Equity Method Investments and Joint Ventures [Abstract] Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] Investment, Name [Axis] Investment, Name [Axis] Investment, Name [Domain] Investment, Name [Domain] Buckeye Wind Energy Class B Holdings, LLC [Member] Buckeye Wind Energy Class B Holdings LLC [Member] Buckeye Wind Energy Class B Holdings LLC [Member] MM Solar Parent, LLC [Member] MM Solar Parent, LLC [Member] MM Solar Parent, LLC [Member] Helix Fund I, LLC [Member] Helix Fund I, LLC [Member] Helix Fund I, LLC [Member] Other Investments [Member] Other Equity Method Investments [Member] Other Equity Method Investments [Member] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Balance Sheet Equity Method Investment, Summarized Financial Information, Liabilities and Equity [Abstract] Current assets Equity Method Investment, Summarized Financial Information, Current Assets Total assets Equity Method Investment, Summarized Financial Information, Assets Current liabilities Equity Method Investment, Summarized Financial Information, Current Liabilities Total liabilities Equity Method Investment, Summarized Financial Information, Liabilities Members’ equity Equity Method Investment Summarized Financial Information, Equity Income Statement Equity Method Investment, Summarized Financial Information, Income Statement [Abstract] Revenue Equity Method Investment, Summarized Financial Information, Revenue Income from continuing operations Equity Method Investment, Summarized Financial Information, Income (Loss) from Continuing Operations Net income Equity Method Investment, Summarized Financial Information, Net Income (Loss) Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Equity [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2013 Plan [Member] Two Thousand And Thirteen Stock Compensation Plan [Member] Two Thousand And Thirteen Stock Compensation Plan [Member] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Restricted Stock and Restricted Stock Units [Member] Restricted Stock And Restricted Stock Units [Member] Restricted stock and restricted stock units. Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Employees and Directors [Member] Employees And Directors [Member] Employees And Directors [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Number of awards authorized for issuance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Number of awards remaining available for issuance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Shares awarded (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Unrecognized compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options Weighted-average term in which unrecognized compensation expense is expected to be recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Transfers and Servicing [Abstract] Schedule of Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Table] Schedule of Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Table] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Securitization Trust [Member] Securitization Trust [Member] Securitization Trust [Member] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Residual Assets [Member] Residual Assets [Member] Residual assets. Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items] Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items] Gains on securitizations Gain (Loss) on Securitization of Financial Assets Purchase of receivables securitized Payments To Acquire Accounts Receivable Securitization Payments to Acquire Accounts Receivable Securitization Proceeds from securitizations Proceeds from Accounts Receivable Securitization Residual and servicing assets included in other assets Retained Interest, Fair Value Disclosure Cash received from residual and servicing assets Cash Received From Residual And Servicing Assets Cash received from residual and servicing assets. Statement of Financial Position [Abstract] Non-recourse notes, secured by assets Non Recourse Secured Notes Payable Non Recourse Secured Notes Payable Preferred stock, par value (in usd per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Common stock, par value (in usd per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized (in shares) Common Stock, Shares Authorized Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Securitization of Receivables Securitization Of Receivables [Text Block] Securitization Of Receivables [Text Block] Financial Instruments Owned and Pledged as Collateral [Table] Financial Instruments Owned and Pledged as Collateral [Table] Asset-Backed Non-recourse Debt [Member] Asset Backed Non Recourse Loan [Member] Asset Backed Non Recourse Loan [Member] Other Non-recourse Debt [Member] Other Non-Recourse Debt [Member] Other Non-Recourse Debt [Member] HASI Sustainable Yield Bond 2013-1 [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Two Thousand Thirteen One [Member] Hannon armstrong sustainable infrastructure capital sustainable yield bond two thousand thirteen one. ABS Loan Agreement [Member] Asset Backed Securities Loan Agreement [Member] Asset backed securities loan agreement. HASI Sustainable Yield Bond 2015-1A [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Two Thousand Fifteen One A [Member] Hannon armstrong sustainable infrastructure capital sustainable yield bond two thousand fifteen one A. HASI Sustainable Yield Bond 2015-1B [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Two Thousand Fifteen One B [Member] Hannon armstrong sustainable infrastructure capital sustainable yield bond two thousand fifteen one B. 2017 Credit Agreement [Member] Two Thousand Seventeen Credit Agreement [Member] 2017 Credit Agreement. HASI SYB Loan Agreement 2015-2 [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Fifteen Two [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Fifteen Two [Member] HASI SYB Loan Agreement 2015-3 [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Fifteen Three [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Fifteen Three [Member] HASI SYB Loan Agreement 2016-1 [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Sixteen One [Member] Hannon armstrong sustainable infrastructure capital sustainable yield bond loan agreement two thousand sixteen one [Member] HASI SYB Trust 2016-2 [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Trust Two Thousand Sixteen Two [Member] Hannon Armstrong sustainable infrastructure capital sustainable yield bond trust two thousand sixteen two [Member] 2017 Master Repurchase Agreement [Member] Two Thousand Seventeen Master Repurchase Agreement [Member] 2017 master repurchase agreement. HASI ECON 101 Trust [Member] HASI ECON 101 Trust [Member] HASI ECON 101 Trust. HASI SYB Trust 2017-1 [Member] HASI SYB Trust 2017-1 [Member] HASI SYB Trust 2017-1 [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum [Member] Minimum [Member] Maximum [Member] Maximum [Member] Extinguishment of Debt [Axis] Extinguishment of Debt [Axis] Extinguishment of Debt, Type [Domain] Extinguishment of Debt, Type [Domain] Restricted Cash and Cash Equivalents [Axis] Restricted Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Collateral Pledged [Member] Collateral Pledged [Member] Financial Instruments Owned and Pledged as Collateral [Line Items] Financial Instruments Owned and Pledged as Collateral [Line Items] Outstanding Balance Long-term Debt, Gross Other non-recourse debt Other Non Recourse Debt Other Non Recourse Debt Debt issuance costs Debt Issuance Costs, Net Total debt Interest Rate Anticipated Balance at Maturity Debt Principal Amount Due Upon Maturity Debt Principal Amount Due Upon Maturity Carrying Value of Assets Pledged, Receivables Pledged Assets, Not Separately Reported, Finance Receivables Carrying Value of Assets Pledged, Other Pledged Assets, Not Separately Reported, Other Costs related to debt repayment Gain (Loss) on Extinguishment of Debt Total collateral pledged against our nonrecourse debt Pledged Financial Instruments, Not Separately Reported, Securities Restricted cash Restricted Cash Income Tax Disclosure [Abstract] Income Tax Contingency [Table] Income Tax Contingency [Table] Distribution Type [Axis] Distribution Type [Axis] Distribution Type [Domain] Distribution Type [Domain] Ordinary Income [Member] Ordinary Income [Member] Ordinary Income [Member] Return of Capital [Member] Return Of Capital [Member] Return Of Capital [Member] Income Tax Contingency [Line Items] Income Tax Contingency [Line Items] Common distributions Effective Income Tax Rate Reconciliation, Deduction, Percent [Abstract] Cash dividend paid Effective Income Tax Rate Reconciliation, Deduction, Dividend, Percent Total Effective Income Tax Rate Reconciliation, Deduction, Percent Restricted Stock [Member] Restricted Stock [Member] Restricted Stock Units [Member] Restricted Stock Units (RSUs) [Member] 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 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 Ending Balance (in shares) Weighted Average Share Price Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Beginning Balance (in 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 (in 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 Vested (in 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 (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Ending Balance (in usd per share) Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value [Abstract] Beginning Balance Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Fair Value One Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Fair Value One Granted Share Based Compensation Arrangement By Share Based Payment Award Equity Instrument Other Than Options Grants In Period Fair Value Share based compensation arrangement by share based payment award equity instrument other than options grants in period fair value. Vested Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Fair Value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Fair Value Forfeited Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Fair Value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeitures Fair Value Ending Balance Equity Stockholders' Equity Note Disclosure [Text Block] Total revenue Revenues Total expenses Operating And Non Operating Expenses Sum of operating and non-operating costs including investment interest expense, compensation and benefits and general and administrative. Income before equity method investments Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Income (loss) from equity method investments Income (Loss) from Equity Method Investments Income before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income tax (expense) benefit Income Tax Expense (Benefit) Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net income (loss) attributable to controlling stockholders Basic and diluted earnings (loss) per common share (in usd per share) Earnings Per Share, Basic and Diluted Investment Portfolios [Abstract] Investment Portfolios [Abstract] 2007 Vento I, LLC [Member] Vento I, LLC [Member] Vento I, LLC. Northern Frontier, LLC [Member] Northern Frontier LLC [Member] Northern Frontier LLC. 3D Engie, LLC [Member] 3D Engie, LLC [Member] 3D Engie, LLC [Member] Invenergy Gunsight Mountain Holdings, LLC [Member] Invenergy Gunsight Mountain Holdings LLC [Member] Invenergy Gunsight Mountain Holdings LLC. Helix Fund I, LLC [Member] Helix Fund, LLC [Member] Helix Fund, LLC [Member] Other Transactions [Member] Carrying Value Equity Method Investments Income Statement [Abstract] Revenue Revenues [Abstract] Interest income, receivables Interest Income, Operating Interest income, investments Investment Income, Interest Rental income Operating Leases, Income Statement, Lease Revenue Gain on sale of receivables and investments Loans and Leases Receivable, Gain (Loss) on Sales, Net Fee income Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions Total revenue Expenses Operating And Non Operating Expenses [Abstract] Operating And Non Operating Expenses [Abstract] Interest expense Interest Expense Compensation and benefits Labor and Related Expense General and administrative General and Administrative Expense Total expenses Net income (loss) attributable to non-controlling interest holders Net Income (Loss) Attributable to Noncontrolling Interest Net income (loss) attributable to controlling stockholders Weighted average common shares outstanding-basic (in shares) Weighted average common shares outstanding-diluted (in shares) Investment [Table] Investment [Table] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Axis] Financing Receivable Portfolio Segment [Domain] Financing Receivable Portfolio Segment [Domain] Real Estate Portfolio [Member] Commercial Real Estate Portfolio Segment [Member] Joint Venture [Member] Corporate Joint Venture [Member] Real Estate Property Ownership [Axis] Real Estate Property Ownership [Axis] Real Estate Properties [Domain] Real Estate Properties [Domain] Lease Intangibles [Member] Real Estate Related Intangibles [Member] Real Estate Related Intangibles [Member] Investment [Line Items] Investment [Line Items] Area of land purchased (in acres) Area of Land Number of solar projects Number Of Solar Projects Number of solar projects. Cost to acquire other real estate Payments to Acquire Other Real Estate Real estate portfolio acquired value through equity interest in joint venture Payments to Acquire Interest in Joint Venture Portfolio cost Payments to Acquire Real Estate Asset Class [Axis] Asset Class [Axis] Asset Class [Domain] Asset Class [Domain] Investment Contracts [Member] Investment Contracts [Member] Portfolio of Behind-the-meter Solar Projects [Member] Portfolio Of Behind-The-Meter Solar Projects [Member] Portfolio Of Behind-The-Meter Solar Projects [Member] Investment in Solar Projects in U.S. Virgin Islands [Member] Investment In Solar Projects In U.S. Virgin Islands [Member] Investment In Solar Projects In U.S. Virgin Islands [Member] Wind Projects [Member] Wind Projects [Member] Wind Projects [Member] Loss from equity method investments Sale of equity interest Proceeds from Sale of Equity Method Investments Equity method investments Equity interest acquired in joint venture Cash received from the investment Proceeds from Equity Method Investment, Distribution OTTI on equity method investments Equity Method Investment, Other than Temporary Impairment Accounting Policies [Abstract] Performance target rate Share-Based Compensation Arrangements By Share-Based Payment Award, Performance Target Rate Share-Based Compensation Arrangements By Share-Based Payment Award, Performance Target Rate Line of Credit Facility [Table] Line of Credit Facility [Table] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Senior Secured Revolving Credit Facility [Member] Revolving Credit Facility [Member] Rep-Based Facility [Member] Representation-Based Facility [Member] Representation-Based Facility [Member] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] 2019 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2020 Long-term Debt, Maturities, Repayments of Principal in Year Two 2021 Long-term Debt, Maturities, Repayments of Principal in Year Three 2022 Long-term Debt, Maturities, Repayments of Principal in Year Four 2023 Long-term Debt, Maturities, Repayments of Principal in Year Five Summary of Dividends Declared by Board of Directors Dividends Declared [Table Text Block] Schedule of Common Stock Public Offerings and ATM Public Offering Of Common Stock [Table Text Block] Public offering of common stock table. Summary of Equity-based Compensation Expense and Fair Value of Shares Vested on Vesting Date Disclosure of Share-based Compensation Arrangements by Share-based Payment Award [Table Text Block] Summary of Unvested Shares of Restricted Common Stock Nonvested Restricted Stock Shares Activity [Table Text Block] Earnings per Share of Common Stock Earnings Per Share [Text Block] Equity Method Investments Equity Method Investments and Joint Ventures Disclosure [Text Block] Number of segment reported Number of Reportable Segments Approval-Based Facility [Member] Approval-Based Facility [Member] Approval-Based Facility [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] LIBOR [Member] London Interbank Offered Rate (LIBOR) [Member] Federal Funds Rate [Member] Federal Funds Effective Swap Rate [Member] Investment Type [Axis] Investment Type [Axis] Investments [Domain] Investments [Domain] U.S. Federal Government [Member] Us Federal Government [Member] Us Federal Government [Member] Institutional [Member] Institutional [Member] Institutional [Member] Certain Approved Existing Financing [Member] Certain Approved Existing Financing [Member] Certain Approved Existing Financing [Member] Others as Prescribed by Administrative Agent [Member] Others As Prescribed By Administrative Agent [Member] Others As Prescribed By Administrative Agent [Member] Credit Default Option [Member] Credit Default Option [Member] Number of revolving credit facilities Debt Instrument, Number Of Instruments Debt Instrument, Number Of Instruments Principal amount Line of Credit Facility, Maximum Borrowing Capacity Basis spread on variable rate (as a percent) Debt Instrument, Basis Spread on Variable Rate Fixed interest rate Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate Applicable valuation percentages Valuation Allowance Percentage Valuation Allowance Percentage Unamortized issuance costs Debt Issuance Costs, Line of Credit Arrangements, Gross Availability fee percentage Line Of Credit Facility, Availability Fee Percentage Line Of Credit Facility, Availability Fee Percentage Default underlying financings (percent) Default Underlying Financing Default underlying financing. Schedule of Computation of Basic and Diluted Earnings Per Common Share of Common Stock Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Escrow deposits DFO Secured Future Funding DFO secured future funding. Investment securities pledged as collateral Financial Instruments Owned and Pledged as Collateral by Type [Axis] Financial Instruments Owned and Pledged as Collateral by Type [Axis] Financial Instruments Owned and Pledged as Collateral, Type [Domain] Financial Instruments Owned and Pledged as Collateral, Type [Domain] Financing Receivables and Investments [Member] Financing Receivables And Investments [Member] Financing receivables and Investments. Deferred funding obligations Contractual Obligation Non-recourse Debt [Member] Non Recourse Notes [Member] Non recourse notes. Future minimum maturities Long-term Debt, Fiscal Year Maturity [Abstract] Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Total minimum maturities Long Term Debt Minimum Maturities Long term debt minimum maturities. Deferred financing costs, net Income Taxes Additional Information [Table] Income Taxes Additional Information [Table] Income Taxes Additional Information [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] TRS [Member] Real Estate Investment Trust Subsidiaries [Member] Real Estate Investment Trust Subsidiaries [Member] Tax Period [Axis] Tax Period [Axis] Tax Period [Domain] Tax Period [Domain] Tax Year 2034 [Member] Tax Year 2034 [Member] Tax Year 2034 [Member] Income Taxes Additional Information [Line Items] Income Taxes Additional Information [Line Items] Income Taxes Additional Information [Line Items] Net deferred tax liabilities Deferred Tax Liabilities, Net Net operating loss carryforwards Operating Loss Carryforwards Deferred tax assets, operating loss carryforwards, subject to expiration Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration Operating loss carryforwards, not subject to expiration Deferred Tax Assets, Operating Loss Carryforwards, Not Subject to Expiration Uncertain tax positions Uncertain Tax Positions Uncertain Tax Positions Accrued interest and penalties Income Tax Examination, Penalties and Interest Accrued Interest and penalties recognized during the period Income Tax Examination, Penalties and Interest Expense Amount per share (in usd per share) Common Stock, Dividends, Per Share, Declared Financing receivable, past due period Threshold Period Past Due For Delinquent Or Nonaccural Of Financing Receivable Threshold period past due for delinquent or nonaccural of financing receivable. Reconciliation Between Statutory Rates and Effective Tax Rates Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Summary of Deferred Tax Assets (Liabilities) Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Cash Dividends Paid for Federal Income Tax Purposes Schedule Of Cash Dividends Paid For Income Tax Purposes [Table Text Block] Schedule Of Cash Dividends Paid For Income Tax Purposes [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement [Member] Portion at Fair Value Measurement [Member] Fair Value [Member] Estimate of Fair Value Measurement [Member] Carrying Value [Member] Reported Value Measurement [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Level 3 [Member] Fair Value, Inputs, Level 3 [Member] Level 2 [Member] Fair Value, Inputs, Level 2 [Member] Government Receivables [Member] Government Receivables [Member] Government Receivables [Member] Commercial Receivables [Member] Commercial Receivables [Member] Commercial Receivables [Member] Receivables Held-For-Sale [Member] Receivables Held-For-Sale [Member] Receivables Held-For-Sale [Member] Investments [Member] Investments [Member] Securitization Residual Assets [Member] Securitization Residual Assets [Member] Securitization residual assets. Credit Facility [Member] Credit Facility [Member] Credit Facility [Member] Convertible Notes [Member] Convertible Debt [Member] 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] Assets Assets, Fair Value Disclosure Liabilities Financial and Nonfinancial Liabilities, Fair Value Disclosure Amortized cost Available-for-sale Debt Securities, Amortized Cost Basis Total interest expense Impact of hedging Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net Hedging Relationship [Axis] Hedging Relationship [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Cash Flow Hedging [Member] Cash Flow Hedging [Member] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Interest Rate Swap [Member] Interest Rate Swap [Member] Gain on settlement of derivatives Gain (Loss) on Sale of Derivatives Receivables Financing Receivable, Additional Disclosures [Abstract] Maturities by period Financing Receivables, Fiscal Year Maturity [Abstract] Financing Receivables, Fiscal Year Maturity [Abstract] Total Financing Receivables Financing Receivables Less than 1 year Financing Receivable Due Less Than One Year Financing Receivable Due Less Than One Year 1-5 years Financing Receivable Due One To Five Years Financing Receivable Due One To Five Years 5-10 years Financing Receivable Due Five To Ten Years Financing Receivable Due Five To Ten Years More than 10 years Financing Receivable Due More Than Ten Years Financing Receivable Due More Than Ten Years Weighted average yield by period Financing Receivables, Weighted Average Yield, Fiscal Year Maturity [Abstract] Financing Receivables, Weighted Average Yield, Fiscal Year Maturity [Abstract] Total Financing Receivables Weighted Average Yield Financing receivables weighted average yield. Less than 1 year Financing Receivables Weighted Average Yield Due Less Than One Year Financing receivables weighted average yield due less than one year. 1-5 years Financing Receivables Weighted Average Yield Due One To Five Years Financing receivables weighted average yield due one to five years. 5-10 years Financing Receivables Weighted Average Yield Due Five To Ten Years Financing receivables weighted average yield due five to ten years. More than 10 years Financing Receivables Weighted Average Yield Due More Than Ten Years Financing receivables weighted average yield due more than ten years. Investments Investments [Abstract] Maturities by period Investments, Fiscal Year Maturity [Abstract] Investments, Fiscal Year Maturity [Abstract] Total Investments Less than 1 year Investments Due Less Than One Year Investments Due Less Than One Year 1-5 years Investments Due One To Five Years Investments Due One To Five Years 5-10 years Investments Due Five To Ten Years Investments Due Five To Ten Years More than 10 years Investments Due More Than Ten Years Investments Due More Than Ten Years Weighted average yield by period Investments, Weighted Average Yield, Fiscal Year Maturity [Abstract] Investments, Weighted Average Yield, Fiscal Year Maturity [Abstract] Total Investments Weighted Average Yield Investments weighted average yield. Less than 1 year Investments Weighted Average Yield Due Less Than One Year Investments weighted average yield due less than one year. 1-5 years Investments Weighted Average Yield Due One To Five Years Investments Weighted Average Yield Due One To Five Years 5-10 years Investments Weighted Average Yield Due Five To Ten Years Investments Weighted Average Yield Due Five To Ten Years More than 10 years Investments Weighted Average Yield Due More Than Ten Years Investments weighted average yield due more than ten years. Outstanding balance Long-term Line of Credit Value of collateral pledged to credit facility Pledged Assets Separately Reported, Finance Receivables Pledged as Collateral, at Fair Value Weighted average short-term borrowing rate Short-term Debt, Weighted Average Interest Rate, at Point in Time Estimated Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value [Abstract] Securities with a loss shorter than 12 months Debt Securities, Available-For-Sale, Unrealized Loss Position Debt Securities, Available-For-Sale, Unrealized Loss Position Securities with a loss longer than 12 months Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer Unrealized Losses Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss [Abstract] Securities with a loss shorter than 12 months Debt Securities, Available-For-Sale, Unrealized Loss Position, Accumulated Loss Debt Securities, Available-For-Sale, Unrealized Loss Position, Accumulated Loss Securities with a loss longer than 12 months Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Accumulated Loss Debt Securities, Available-For-Sale, Continuous Unrealized Loss Position, 12 Months Or Longer, Accumulated Loss Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Schedule of Financing Receivable, Recorded Investment, Credit Quality Indicator [Table] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Axis] Class of Financing Receivable, Type [Domain] Class of Financing Receivable, Type [Domain] Government [Member] US Treasury and Government [Member] Subtotal, Debt and Real Estate [Member] Debt And Real Estate Portfolio Rated Investment Grade Excluding Equity Method Investments [Member] Debt And Real Estate Portfolio Rated Investment Grade Excluding Equity Method Investments [Member] Equity Method Investments [Member] Equity Method Investments [Member] State, Local, Institutions [Member] US States and Political Subdivisions Debt Securities [Member] Residential Solar Loan [Member] Residential Solar Loan [Member] Residential solar loan. External Credit Rating by Grouping [Axis] External Credit Rating by Grouping [Axis] External Credit Rating by Grouping [Domain] External Credit Rating by Grouping [Domain] Commercial Investment Grade [Member] External Credit Rating, Investment Grade [Member] Commercial Non-Investment Grade [Member] External Credit Rating, Non Investment Grade [Member] Renewable Energy Projects [Member] Renewable Energy Projects [Member] Renewable energy projects. Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Credit Concentration Risk [Member] Credit Concentration Risk [Member] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Debt and Real Estate Portfolio [Member] Portfolio [Member] Portfolio [Member] Internal Credit Assessment [Axis] Internal Credit Assessment [Axis] Internal Credit Assessment [Domain] Internal Credit Assessment [Domain] Investment Grade by Independent Rating Agency [Member] Investment Grade By Independent Rating Agency [Member] Investment Grade By Independent Rating Agency [Member] SunStrong [Member] Subsidiaries Of SunPower Corporation [Member] Subsidiaries of SunPower Corporation. Financing Receivable, Recorded Investment [Line Items] Financing Receivable, Recorded Investment [Line Items] Receivables Loans and Leases Receivable, Gross Real estate Real Estate Investments And Intangible Leases Assets Real Estate Investments And Intangible Leases Assets Investments Available-for-sale Securities, Debt Securities Total Long-term Investments and Receivables, Net % of Debt and real estate portfolio Concentration Risk, Percentage Average remaining balance Finance Receivable Outstanding Average Remaining Balance Finance Receivable Outstanding Average Remaining Balance Total financing receivable Loans and Leases Receivable, Net Amount Loans receivable Loans Receivable, Net Increase in finance receivables Increase (Decrease) in Finance Receivables Financing receivables on non accrual status Financing Receivable, Recorded Investment, Nonaccrual Status Number of transactions Number of Transactions Number of Transactions Total aggregate remaining balance Finance Receivable Aggregate Remaining Amount Finance Receivable Aggregate Remaining Amount Statement of Comprehensive Income [Abstract] Net income (loss) Unrealized gain (loss) on available-for-sale securities, net of tax (provision) benefit of $0.1 million, $0.1 million and $0.0 million in 2018, 2017, and 2016 respectively Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Unrealized gain (loss) on interest rate swaps, net of tax (provision) benefit of $0.0 million in 2018, 2017, and 2016 Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Comprehensive income (loss) Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Less: Comprehensive income (loss) attributable to non-controlling interest holders Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Comprehensive income (loss) attributable to controlling stockholders Comprehensive Income (Loss), Net of Tax, Attributable to Parent Retirement Benefits [Abstract] Defined Contribution Plan Pension and Other Postretirement Benefits Disclosure [Text Block] Defined Contribution Plan [Table] Defined Contribution Plan [Table] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] First 4% of Employee's Contribution [Member] Level One [Member] Level One [Member] Next 2% of Employee's Contribution [Member] Levels Two [Member] Levels Two [Member] Defined Contribution Plan Disclosure [Line Items] Defined Contribution Plan Disclosure [Line Items] Defined contribution plan, employer's matching contribution, percentage of match Defined Contribution Plan, Employer Matching Contribution, Percent of Match Defined contribution plan, employer matching contribution, percent of employees' gross pay Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Contribution plan cost (less than) Defined Contribution Plan, Cost Restricted Incentive [Member] Equity-based compensation expense Employee Benefits and Share-based Compensation Fair value of awards vested on vesting date Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Fair Value, Option, Qualitative Disclosures Related to Election [Table] Fair Value, Option, Qualitative Disclosures Related to Election [Table] Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] Fair Value, Option, Qualitative Disclosures Related to Election [Line Items] Fair value interest rate spreads, minimum Fair Value Interest Rate Spreads Minimum Fair Value Interest Rate Spreads Minimum Fair value interest rate spreads, maximum Fair Value Interest Rate Spreads Maximum Fair Value Interest Rate Spreads Maximum Cash deposits Cash and Cash Equivalents, at Carrying Value Restricted cash deposits (included in other assets) Restricted Cash and Cash Equivalents Total cash deposits Cash and Cash Equivalents, Fair Value Disclosure Amount of cash deposits in excess of amounts federally insured Cash, Uninsured Amount Rent expense (less than) Operating Leases, Rent Expense Future gross minimum lease payments (less than) Operating Leases, Future Minimum Payments Due Summary of Certain Transactions with Securitization Trusts Schedule Of Cash Flows Received From And Paid To Loan Securitization Trusts [Table Text Block] Schedule of cash flows received from and paid to loan securitization trusts table text block. Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Debt Securities [Member] Debt Securities [Member] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Balance, beginning of period Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Purchases of investments Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Payments on investments Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements Transfers to investments Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Unrealized gains (losses) on investments recorded in OCI Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Balance, end of period Summary of Fair Value and Carrying Value of Financial Assets and Liabilities Fair Value, Option, Qualitative Disclosures Related to Election [Table Text Block] Schedule of Reconciliation of Level 3 Investments Securities Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Schedule of Investments in Unrealized Loss Position Debt Securities Available For Sale Unrealized Loss Position Fair Value [Table Text Block] Tabular disclosure of fair value amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position. Schedule of Cash Deposits Subject to Credit Risk Fair Value, Concentration of Risk [Table Text Block] Term Loan [Member] Secured Debt [Member] Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Loans Payable [Member] Loans Payable [Member] Proceeds from borrowings Proceeds from Lines of Credit Short-term loans borrowed Short-term Debt Statement of Cash Flows [Abstract] Cash flows from operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] 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] Depreciation and amortization Depreciation, Depletion and Amortization Equity-based compensation Share-based Compensation Equity method investments Income (Loss) from Equity Method Investments, Net of Dividends or Distributions Non-cash gain on securitization Gain on sale of receivables and investments Gain (Loss) On Sale of Receivables and Investments Gain (loss) on sale of receivables and investments. Changes in receivables held-for-sale Loans Receivable Held-for-sale, Reconciliation to Cash Flow, Period Increase (Decrease) Loss on debt extinguishment Changes in accounts payable and accrued expenses Increase (Decrease) in Accounts Payable and Accrued Liabilities Other Increase (Decrease) in Other Operating Assets 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] Equity method investments Payments to Acquire Equity Method Investments Equity method distributions received Proceeds from Equity Method Investment, Distribution, Return of Capital Proceeds from sales of equity method investments Purchases of receivables Payments to Acquire Finance Receivables Principal collections from receivables Proceeds from Collection of Finance Receivables Proceeds from sales of receivables Proceeds from Sale of Finance Receivables Purchases of real estate Payments to Acquire and Develop Real Estate Purchases of investments Payments to Acquire Available-for-sale Securities Principal collections from investments Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Proceeds from sales of investments Proceeds from Sale of Available-for-sale Securities Funding of escrow accounts Payments For Funding Of Escrow Accounts Payments for funding of escrow accounts. Withdrawal from escrow accounts Proceeds From Escrow Accounts Proceeds from escrow accounts. Other Payments for (Proceeds from) Other Investing Activities 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] Proceeds from credit facilities Principal payments on credit facilities Repayments of Lines of Credit Proceeds from issuance of non-recourse debt Proceeds from Issuance of Secured Debt Principal payments on non-recourse debt Repayments of Secured Debt Proceeds from issuance of convertible notes Proceeds from Convertible Debt Payments on deferred funding obligations Payments on Deferred Funding Obligations Payments on Deferred Funding Obligations Net proceeds of common stock issuances Proceeds from Issuance of Common Stock Payments of dividends and distributions Payments of Dividends Other Proceeds from (Payments for) Other Financing Activities Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Increase (decrease) in cash, cash equivalents, and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Cash, cash equivalents, and restricted cash at beginning of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, cash equivalents, and restricted cash at end of period Interest paid Interest Paid Non-cash changes in deferred funding obligations (financing activity) Non Cash Changes In Deferred Funding Obligations Non cash changes in deferred funding obligations. Non-cash changes in non-recourse debt (financing activity) Noncash or Part Noncash Acquisition, Debt Assumed Non-cash changes in receivables and investments (investing activity) Non Cash Changes In Financing Receivables And Investments Non-cash changes in financing receivables and investments. Non-cash changes in residual assets (investing activity) Gain Loss On Non Cash Securitization Of Residual Assets Gain loss on non cash securitization of residual assets. Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common Stock [Member] Additional Paid-in Capital [Member] Additional Paid-in Capital [Member] Accumulated Deficit [Member] Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) [Member] AOCI Attributable to Parent [Member] Non-Controlling Interest [Member] Noncontrolling Interest [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning Balance (in shares) Shares, Outstanding Beginning Balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Net income Unrealized gain (loss) on available-for-sale securities Unrealized gain (loss) on interest rate swaps Impact of adoption of ASU 2017-12 New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification Issued shares of common stock (in shares) Stock Issued During Period, Shares, New Issues Issued shares of common stock Stock Issued During Period, Value, New Issues Equity-based compensation Stock Granted, Value, Share-based Compensation, Net of Forfeitures Issuance (repurchase) of vested equity-based compensation shares (in shares) Vested Equity Based Compensation Shares Issued And Other Adjustments Vested Equity Based Compensation Shares Issued And Other Adjustments Issuance (repurchase) of vested equity-based compensation shares Vested Equity Based Compensation Shares Issued And Other Adjustments Amount Vested Equity Based Compensation Shares Issued And Other Adjustments Amount Redemption of OP units (in shares) Stock Redeemed or Called During Period, Shares Redemption of OP units Stock Redeemed or Called During Period, Value Dividends and distributions Dividends, Common Stock, Cash Ending Balance (in shares) Ending Balance Schedule of Outstanding Non-Recourse Asset-Backed Debt and Bank Loans Schedule of Financial Instruments Owned and Pledged as Collateral [Table Text Block] Schedule of Interest Rate Swaps which are Designated as Cash Flow Hedges Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Summary of Presentation of Total Balance of Financial Statement Line Item Related to Hedging Activities in Consolidated Statements of Operations and Impact of Hedges Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location [Table Text Block] Schedule of Minimum Maturities of Non-Recourse Debt Schedule of Maturities of Long-term Debt [Table Text Block] Summary of Components of Convertible Notes Convertible Debt [Table Text Block] Schedule of Equity Method Investments Equity Method Investments [Table Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] The Company Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Financing receivables, investments, real estate and equity method investments Noncontrolling Interest [Abstract] Noncontrolling Interest [Table] Noncontrolling Interest [Table] Noncontrolling Interest [Line Items] Noncontrolling Interest [Line Items] Outstanding OP units held by outside limited partners (as a percent) Operating Partnership Units Not Owned By Company Operating partnership units not owned by company. Exchange of operating partnership units to common stock Exchange Of Operating Partnership Units To Common Stock Exchange of operating partnership units to common stock. Payment in cash for redemption of operating partnership units Payments for Repurchase of Redeemable Noncontrolling Interest Schedule of Financing Receivables Past Due [Table] Schedule of Financing Receivables Past Due [Table] Investment Grade [Member] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] American Wind Capital Company, LLC [Member] American Wind Capital Company, LLC [Member] American Wind Capital Company, LLC [Member] Property Subject to or Available for Operating Lease [Axis] Property Subject to or Available for Operating Lease [Axis] Property Subject to or Available for Operating Lease [Domain] Property Subject to or Available for Operating Lease [Domain] Land [Member] Land [Member] Financing Receivable, Recorded Investment, Past Due [Line Items] Financing Receivable, Recorded Investment, Past Due [Line Items] Collections of loans Proceeds from Collection of Loans Receivable Principal payments on non-recourse debt Proceeds from pre-payment premium Proceeds From Pre-Payment Premiums On Non Recourse Debt Proceeds From Pre-Payment Premiums On Non Recourse Debt Unamortized loan costs and fees Unamortized Loan Commitment and Origination Fees and Unamortized Discounts or Premiums Commercial receivables, carrying value that became past due Financing Receivable, Recorded Investment, Past Due Proceeds from lease payments Proceeds from Collection of Lease Receivables Provision for credit losses Provision for Loan and Lease Losses Loan modifications that qualify as troubled debt restructurings Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down Unrealized gain (loss) on available-for-sale securities, (provision) benefit Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax Unrealized gain (loss) on interest rate swaps, tax (provision) benefit Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax Schedule of Securitization or Asset-backed Financing Arrangements, Financial Asset for which Transfer is Accounted as Sale [Table] Schedule of Securitization or Asset-backed Financing Arrangements, Financial Asset for which Transfer is Accounted as Sale [Table] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Asset-backed Securities, Securitized Loans and Receivables [Member] Asset-backed Securities, Securitized Loans and Receivables [Member] Financing Receivables, Period Past Due [Axis] Financing Receivables, Period Past Due [Axis] Financing Receivables, Period Past Due [Domain] Financing Receivables, Period Past Due [Domain] Greater than 90 Days Past Due [Member] Financing Receivables, Equal to Greater than 90 Days Past Due [Member] Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items] Securitization or Asset-backed Financing Arrangement, Financial Asset for which Transfer is Accounted as Sale [Line Items] Annual servicing fees (as a percent) Services Fee Annual Rate Services Fee Annual Rate Discount rates to determine fair market value of underlying assets Fair Value Inputs, Discount Rate Managed assets Managed Assets Managed Assets Managed receivables Receivables Serviced Receivables Serviced Securitization credit losses Net Credit Loss on Loans Managed or Securitized or Asset-backed Financing Arrangement Payment from debtors to securitization trust Accounts Receivable from Securitization Credit Facilities Credit Facility Disclosure [Text Block] Credit Facility Disclosure [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Consolidation and Equity Method Investments Consolidation And Equity Method Investment In Affiliate [Policy Text Block] Consolidation and equity method investment in affiliate. Government and Commercial Receivables Receivables, Policy [Policy Text Block] Real Estate Real Estate, Policy [Policy Text Block] Investments Investment, Policy [Policy Text Block] Securitization of Receivables Securitizations [Policy Text Block] Securitizations Policy [Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Convertible Notes Convertible Notes [Policy Text Block] Convertible notes. Derivative Financial Instruments Derivatives, Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Equity-Based Compensation Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Earnings Per Share Earnings Per Share, Policy [Policy Text Block] Segment Reporting Segment Reporting, Policy [Policy Text Block] Recently Issued Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Receivables basis difference Increase (Decrease) in Notes Receivables Equity method investments Deferred Tax Liabilities, Investment in Noncontrolled Affiliates Gross deferred tax liabilities Deferred Tax Liabilities, Gross Net operating loss (NOL) carryforwards Deferred Tax Assets, Operating Loss Carryforwards Tax credit carryforwards Deferred Tax Assets, Tax Credit Carryforwards Share-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Valuation allowance Deferred Tax Assets, Valuation Allowance Gross deferred tax assets Deferred Tax Assets, Gross Net deferred tax liabilities Future Amortization Expense Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] 2019 Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months 2020 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2021 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2022 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2023 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Five Total Finite-Lived Intangible Assets, Net Minimum Rental Payments Operating Leases, Future Minimum Payments Receivable [Abstract] 2019 Operating Leases, Future Minimum Payments Receivable, Current 2020 Operating Leases, Future Minimum Payments Receivable, in Two Years 2021 Operating Leases, Future Minimum Payments Receivable, in Three Years 2022 Operating Leases, Future Minimum Payments Receivable, in Four Years 2023 Operating Leases, Future Minimum Payments Receivable, in Five Years Thereafter Operating Leases, Future Minimum Payments Receivable, Thereafter Total Operating Leases, Future Minimum Payments Receivable Our Portfolio Portfolio [Text Block] Disclosure for portfolio, including financing receivables, investments available for sale, real estate, and equity method investments. Long-term Debt Long-term Debt [Text Block] Debt Instruments [Abstract] Accrued interest Debt Instrument Accrued Interest Debt instrument accrued interest. Unamortized financing costs Unamortized Debt Issuance Expense Carrying value of convertible notes Federal statutory income tax rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Share based compensation Effective Income Tax Rate Reconciliation, Deductions, Share-based Compensation Cost, Percent Effective Income Tax Rate Reconciliation, Deductions, Share-based Compensation Cost, Percent Equity method investments Effective Income Tax Rate Reconciliation Equity Method Investments Earnings Losses Effective income tax rate reconciliation equity method investments earnings losses. Other Effective Income Tax Rate Reconciliation,Other Reconciling Items, Percent Valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent TCJA rate revaluation adjustment Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent Effective tax rate Effective Income Tax Rate Reconciliation, Percent Assets Assets [Abstract] Government receivables Government Contract Receivable Commercial receivables Loans Receivable, Gross, Commercial and Industrial Receivables held-for-sale Loans Receivable Held-for-sale, Net, Not Part of Disposal Group Real estate Real Estate Investments, Net Investments Available-for-sale Securities Cash and cash equivalents Other assets Other Assets Total Assets Assets Liabilities and Stockholders’ Equity Liabilities and Equity [Abstract] Liabilities: Liabilities [Abstract] Accounts payable, accrued expenses and other Accounts Payable and Accrued Liabilities Credit facilities Non-recourse debt (secured by assets of $1,105 million and $1,545 million, respectively) Non-Recourse Debt Convertible notes Convertible Notes Payable Total Liabilities Liabilities Stockholders’ Equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, par value $0.01 per share, 50,000,000 shares authorized, no shares issued and outstanding Preferred Stock, Value, Issued Common stock, par value $0.01 per share, 450,000,000 shares authorized, 60,510,086 and 51,665,449 shares issued and outstanding, respectively Common Stock, Value, Issued Additional paid in capital Additional Paid in Capital, Common Stock Accumulated deficit Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Non-controlling interest Stockholders' Equity Attributable to Noncontrolling Interest Total Stockholders’ Equity Total Liabilities and Stockholders’ Equity Liabilities and Equity Fair Value Measurements Fair Value Disclosures [Text Block] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Sale of Stock [Axis] Sale of Stock [Axis] Sale of Stock [Domain] Sale of Stock [Domain] ATM [Member] At the Market Offering [Member] At the Market Offering [Member] Public Offering [Member] Public Offering [Member] Public Offering [Member] Shares Issued (in shares) Price Per Share (in usd per share) Sale of Stock, Price Per Share Net Proceeds Analysis of Portfolio by Type of Obligor and Credit Quality Financing Receivable Credit Quality Indicators [Table Text Block] Summary of Anticipated Maturity Dates of Receivables and Investments and Weighted Average Yield Investments Classified by Contractual Maturity Date [Table Text Block] Components of Real Estate Portfolio Schedule of Real Estate Properties [Table Text Block] Schedule of Future Amortization Expenses Related to Intangible Assets and Future Minimum Rental Payments under Land Lease Agreements Schedule Of Finite Lived Intangible Assets Future Amortization Expense And Capital Leased Assets [Table Text Block] Schedule of finite lived intangible assets future amortization expense and capital leased assets. Summary of Outstanding Deferred Funding Obligations to be Paid Contractual Obligation, Fiscal Year Maturity Schedule [Table Text Block] Schedule of Real Estate Properties [Table] Schedule of Real Estate Properties [Table] Real Estate Properties [Line Items] Real Estate Properties [Line Items] Real estate Real Estate Investment Property, Net Accumulated amortization of lease intangibles Real Estate Investment Property, Accumulated Depreciation Non-Controlling Interest Noncontrolling Interest Disclosure [Text Block] Future Payments Contractual Obligation, Fiscal Year Maturity [Abstract] 2019 Contractual Obligation, Due in Second Year 2020 Contractual Obligation, Due in Third Year 2021 Contractual Obligation, Due in Fourth Year Total Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] HASI SYB Loan Agreement 2015-2 A [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Fifteen Twoa [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Fifteen Two A [Member] HASI SYB Loan Agreement 2015-2 B [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Fifteen Twob [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Fifteen Two B [Member] HASI SYB Loan Agreement 2016-1 A [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Sixteen OneA [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond loan agreement two thousand sixteen one - A. HASI SYB Loan Agreement 2016-1 B [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond Loan Agreement Two Thousand Sixteen OneB [Member] Hannon Armstrong Sustainable Infrastructure Capital Sustainable Yield Bond loan agreement two thousand sixteen one - B. Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Hedged Rate Derivative, Fixed Interest Rate Notional Value Derivative, Notional Amount Fair Value Derivative, Fair Value, Net Income Tax Income Tax Disclosure [Text Block] Schedule of Additional Detail on Credit Facility Schedule of Line of Credit Facilities [Table Text Block] Schedule of Minimum Maturities of Debt