Fair Value Disclosures [Abstract] Notes payable, fixed interest rate Long-term Debt, Percentage Bearing Fixed Interest, Percentage Rate Notes payable, aggregate fair value Notes Payable, Fair Value Disclosure Notes payable, principal balance Notes Payable Fair Value of Financial Instruments [Table] Fair Value Of Financial Instruments [Table] Fair Value of Financial Instruments [Table] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Interest Rate Swap Interest Rate Swap [Member] Fair Value of Financial Instruments [Line Items] Fair Value Of Financial Instruments [Line Items] Fair Value of Financial Instruments [Line Items] Fair value of derivative liability Derivative Liability Debt Disclosure [Abstract] Interest incurred Interest Expense, Debt Amortization of deferred debt costs Amortization of Debt Issuance Costs and Discounts Capitalized interest Interest Costs Capitalized Adjustment Interest expense and amortization of deferred debt costs Noncash Interest Expense Accretion And Amortization Of Deferred Finance Fees Noncash Interest Expense Accretion And Amortization Of Deferred Finance Fees Document And Entity Information [Abstract] Document And Entity Information [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Trading Symbol Trading Symbol Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Related Party Transactions [Abstract] Related Party Transactions Related Party Transactions Disclosure [Text Block] Segment Reporting [Abstract] Number of reportable business segments Number of Reportable Segments Equity [Abstract] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Series C Cumulative Preferred Stock Series C Cumulative Preferred Stock [Member] Series C Cumulative Preferred Stock [Member] Series D Cumulative Redeemable Preferred Stock Series D Cumulative Redeemable Preferred Stock [Member] Series D Cumulative Redeemable Preferred Stock [Member] Class of Stock [Line Items] Class of Stock [Line Items] Income attributable to noncontrolling interests Income (Loss) Attributable to Noncontrolling Interest, before Tax Depositary shares outstanding (in shares) Preferred Stock, Depositary Shares Outstanding Preferred Stock, Depositary Shares Outstanding Net proceeds from shares sold Net Proceeds From Shares Sold Net Proceeds From Shares Sold Depository shares to cumulative redeemable preferred stock ratio Depository Shares To Redeemable Preferred Stock Ratio Depository Shares to Redeemable Preferred Stock Ratio Percentage of redeemable preferred stock Preferred Stock Redemption Percentage Of Originally Issued Shares Preferred Stock Redemption, Percentage of Originally Issued Shares Cumulative redeemable preferred stock liquidation preference (in usd per share) Preferred Stock, Liquidation Preference Per Share Depositary shares redeemed during period (in shares) Depositary Shares Redeemed During Period, Shares Depositary Shares Redeemed During Period, Shares Annual dividend on depositary shares (in usd per share) Depository Shares Dividends Per Share Depository Shares Dividends per Share Income Statement [Abstract] Revenue Revenues [Abstract] Base rent Operating Leases, Income Statement, Minimum Lease Revenue Expense recoveries Tenant Reimbursements Percentage rent Operating Leases, Income Statement, Percentage Revenue Other Other Real Estate Revenue Total revenue Revenues Operating expenses Costs and Expenses [Abstract] Property operating expenses Direct Costs of Leased and Rented Property or Equipment Provision for credit losses Provision for Loan and Lease Losses Real estate taxes Real Estate Tax Expense Interest expense and amortization of deferred debt costs Depreciation and amortization of deferred leasing costs Depreciation, Depletion and Amortization General and administrative General and Administrative Expense Total operating expenses Costs and Expenses Operating income Operating Income (Loss) Change in fair value of derivatives Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Noncontrolling interests Noncontrolling Interest [Abstract] Income attributable to noncontrolling interests Net income attributable to Saul Centers, Inc. Net Income (Loss) Attributable to Parent Extinguishment of issuance costs upon redemption of preferred shares Preferred Stock Redemption Premium Preferred stock dividends Preferred Stock Dividends, Income Statement Impact Net income available to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Per share net income available to common stockholders Earnings Per Share [Abstract] Basic and diluted (in usd per share) Earnings Per Share, Basic and Diluted Dividends declared per common share outstanding (in usd per share) Common Stock, Dividends, Per Share, Declared Balloon Payments Longterm Debt Maturities Balloon Payments [Abstract] Long-term Debt, Maturities, Balloon Payments [Abstract] April 1 through December 31, 2018 Long-term Debt, Maturities, Balloon Payments Remainder Of Fiscal Year Long-term Debt, Maturities, Balloon Payments, Remainder of Fiscal Year 2019 Long-term Debt, Maturities, Balloon Payments In Year Two Long-term Debt, Maturities, Balloon Payments in Year Two 2020 Long-term Debt, Maturities, Balloon Payments In Year Three Long-term Debt, Maturities, Balloon Payments in Year Three 2021 Long-term Debt, Maturities, Balloon Payments in Year Four Long-term Debt Maturities Balloon Payments in Year Four 2022 Long-term Debt, Maturities, Balloon Payments In Year Five Long-term Debt, Maturities, Balloon Payments in Year Five 2023 Long-term Debt, Maturities, Balloon Payments In Year Six Long-term Debt Maturities Balloon Payments In Year Six Thereafter Long-term Debt, Maturities, Balloon Payments After Year Six Long-term Debt Maturities Balloon Payments After Year Six Principal amount Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid Scheduled Principal Amortization Long-term Debt, Fiscal Year Maturity [Abstract] April 1 through December 31, 2018 Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year 2019 Long-term Debt, Maturities, Repayments of Principal in Year Two 2020 Long-term Debt, Maturities, Repayments of Principal in Year Three 2021 Long-term Debt, Maturities, Repayments of Principal in Year Four 2022 Long-term Debt, Maturities, Repayments of Principal in Year Five 2023 Long-term Debt, Maturities, Repayments of Principle in Year Six Long-term Debt, Maturities, Repayments of Principle in Year Six Thereafter Long-term Debt, Maturities, Repayments of Principle After Year Six Long-term Debt, Maturities, Repayments of Principle After Year Six Principal amount Long-term Debt Total Long Term Debt Maturities Repayments Of Principal And Balloon Payments [Abstract] Long-Term Debt, Maturities, Repayments of Principal and Balloon Payments [Abstract] April 1 through December 31, 2018 Long-term Debt, Maturities Repayments Of Principal And Balloon Payments Remainder Of Fiscal Year Long-term Debt, Maturities, Repayments of Principal and Balloon Payments, Remainder of Fiscal Year 2019 Long-term Debt, Maturities, Repayments Of Principal And Balloon Payments In Year Two Long-term Debt, Maturities, Repayments of Principal and Balloon Payments in Year Two 2020 Long-term Debt, Maturities, Repayments Of Principal And Balloon Payments In Year Three Long-term Debt, Maturities, Repayments of Principal and Balloon Payments in Year Three 2021 Long-term Debt, Maturities, Repayments Of Principal And Balloon Payments In Year Four Long-term Debt, Maturities, Repayments of Principal and Balloon Payments in Year Four 2022 Long-term Debt, Maturities, Repayments Of Principal And Balloon Payments In Year Five Long-term Debt, Maturities, Repayments of Principal and Balloon Payments in Year Five 2023 Long-term Debt, Maturities, Repayments Of Principal And Balloon Payments In Year Six Long-term Debt Maturities Repayments Of Principal And Balloon Payments In Year Six Thereafter Long-term Debt, Maturities, Repayments Of Principal And Balloon Payments After Year Six Long-term Debt Maturities Repayments Of Principal And Balloon Payments After Year Six Principal amount Long-term Debt Repayments Of Principal And Balloon Payments Long-term Debt, Repayments of Principal and Balloon Payments Unamortized deferred debt costs Debt Issuance Costs, Net Net Long-term Repayments of Principal and Balloon Payments, Net of Debt Issuance Costs Long-term Repayments of Principal and Balloon Payments, Net of Debt Issuance Costs Equity Stockholders' Equity Note Disclosure [Text Block] Accounting Policies [Abstract] Weighted average common stock outstanding-Basic (in shares) Weighted Average Number of Shares Outstanding, Basic Effect of dilutive options (in shares) Weighted Average Number Diluted Shares Outstanding Adjustment Weighted average common stock outstanding-Diluted (in shares) Weighted Average Number of Shares Outstanding, Diluted Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Options Equity Option [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Non-dilutive options (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award Options [Table] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award Options [Table] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award Options [Table] Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Directors Director [Member] Officers Officer [Member] Period [Axis] Period [Axis] Period [Axis] Period [Domain] Period [Domain] Period [Domain] 4/25/2008 Period Five [Member] Period 5 [Member] 4/24/2009 Period Six [Member] Period 6 [Member] 5/7/2010 Period Seven [Member] Period 7 [Member] 5/13/2011 Period Eight [Member] Period 8 [Member] 5/4/2012 Period Nine [Member] Period 9 [Member] 5/10/2013 Period Ten [Member] Period 10 [Member] 5/9/2014 Period Eleven [Member] Period Eleven [Member] 5/8/2015 May 8, 2015 [Member] May 8, 2015 [Member] 5/6/2016 May 6, 2016 [Member] May 6, 2016 [Member] 5/5/2017 May 5, 2017 [Member] May 5, 2017 [Member] 5/3/2018 May 3, 2018 [Member] May 3, 2018 [Member] Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items] Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items] Share Based Compensation Arrangements By Share Based Payment Award Options [Line Items] Total grant (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Total Grants In Period Gross Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Total Grants in Period, Gross Vested (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Vested In Period Share Based Compensation Arrangement by Share Based Payment Award, Options, Vested in Period Exercised (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Total Exercises In Period Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Total Exercises In Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Exercisable at end of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Remaining unexercised (in shares) Share Based Compensation Arrangement By Share Based Payment Award Options Remaining Unexercised Number Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Remaining Unexercised, Number Exercise price (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Volatility (percentage) Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Volatility Share Based Compensation Arrangement by Share Based Payment Award, Fair Value Assumptions, Volatility Expected life (years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Assumed yield (percentage) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Risk-free rate (percentage) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Total value at grant date Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Fair Value Share based Compensation Arrangement by Share based Payment Award, Options, Grants in Period, Fair Value Estimated forfeitures Share Based Compensation Arrangement By Share Based Payment Award Options Forfeited In Period Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeited in Period, Fair Value Expensed in previous years Allocated Share Based Compensation Expense In Previous Years Allocated Share-Based Compensation Expense in Previous Years Expensed in 2018 Allocated Share-based Compensation Expense Future expense Employee And Non Employee Service Share-Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options Employee and Non Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options Weighted average term of remaining future expense (in years) Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Organization, Consolidation and Presentation of Financial Statements [Abstract] Distribution of REIT taxable income (excluding net capital gains) to its stockholders (percent) Minimum Percentage Of Taxable Income Distribution To Shareholders Minimum Percentage of Taxable Income Distribution to Shareholders Number of partnerships Number of Partnerships Number of Partnerships Organization, Consolidation and Presentation of Financial Statements Disclosure [Table] Organization Consolidation And Presentation Of Financial Statements Disclosure [Table] Organization, Consolidation and Presentation of Financial Statements Disclosure [Table] Real Estate Property Ownership [Axis] Real Estate Property Ownership [Axis] Real Estate Properties [Domain] Real Estate Properties [Domain] Shopping Centers Shopping Centers [Member] Shopping Centers [Member] Mixed-Use Properties Mixed Use Properties [Member] Mixed-Use Properties [Member] Non-operating Development Properties Nonoperating Development Properties [Member] Nonoperating Development Properties [Member] Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] Organization Consolidation And Presentation Of Financial Statements Disclosure [Line Items] Organization, Consolidation and Presentation of Financial Statements Disclosure [Line Items] Number of real estate properties Number of Real Estate Properties Statement of Cash Flows [Abstract] Statement [Table] Statement [Table] Statement [Line Items] Statement [Line Items] 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] Depreciation and amortization of deferred leasing costs Amortization of deferred debt costs Non cash compensation costs of stock grants and options Share-based Compensation Provision for credit losses Provision for Loan, Lease, and Other Losses Decrease in accounts receivable and accrued income Increase (Decrease) in Accounts and Notes Receivable Additions to deferred leasing costs Increase (Decrease) in Deferred Leasing Fees Decrease in prepaid expenses Increase (Decrease) in Prepaid Expense Increase in other assets Increase (Decrease) in Other Operating Assets Increase in accounts payable, accrued expenses and other liabilities Increase Decrease In Accounts Payable Accrued Expenses And Other Liabilities The net change during the reporting period in the aggregate amount of accounts payable accrued expenses and other liabilities incurred but not paid. Increase (decrease) in deferred income Increase (Decrease) in Deferred Income Taxes 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] Acquisitions of real estate investments Payments to Acquire Other Real Estate Additions to real estate investments Payments to Acquire Real Estate Additions to development and redevelopment projects Payments to Develop Real Estate Assets Net cash 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 notes payable Proceeds from Issuance of Secured Debt Repayments on notes payable Repayments of Secured Debt Proceeds from term loan facility Proceeds from Issuance of Medium-term Notes Proceeds from revolving credit facility Proceeds from Lines of Credit Repayments on revolving credit facility Repayments of Lines of Credit Proceeds from construction loan Proceeds from Construction Loans Payable Additions to deferred debt costs Payments of Debt Issuance Costs Proceeds from the issuance of: Proceeds from Issuance or Sale of Equity [Abstract] Common stock Proceeds from Issuance of Common Stock Partnership units Proceeds from Issuance of Common Limited Partners Units Series D preferred stock Proceeds from Issuance of Preferred Stock and Preference Stock Series C preferred stock redemption payment Payments for Repurchase of Redeemable Preferred Stock Preferred stock redemption costs Payment For Preferred Stock Redemption Costs Payment For Preferred Stock Redemption Costs Distributions to: Payments of Dividends [Abstract] Series C preferred stockholders Payments of Ordinary Dividends, Preferred Stock and Preference Stock Common stockholders Payments of Ordinary Dividends, Common Stock Noncontrolling interests Payments of Ordinary Dividends, Noncontrolling Interest Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Net increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents, end of period Supplemental disclosure of cash flow information: Supplemental Cash Flow Information [Abstract] Cash paid for interest Interest Paid Increase (decrease) in accrued real estate investments and development costs Noncash or Part Noncash Increase (Decrease) In Accrued Real Estate Investments And Development Costs Noncash or Part Noncash Increase (Decrease) in Real Estate Investments and Development Costs Schedule of Construction in Progress Schedule of Construction in Progress [Table Text Block] Schedule of Construction in Progress [Table Text Block] Basic and Diluted Shares Outstanding Schedule of Weighted Average Number of Shares [Table Text Block] Stock Option Plans Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Noncontrolling Interest [Table] Noncontrolling Interest [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Noncontrolling Interest Noncontrolling Interest [Member] Noncontrolling Interest [Line Items] Noncontrolling Interest [Line Items] Percentage of ownership interest of noncontrolling interest Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners Limited partnership units (in shares) Limited Partners' Capital Account, Units Outstanding Limited partnership units, conversion ratio Limited Partners Capital Account Convertible Units Conversion Ratio Limited Partners' Capital Account, Convertible Units, Conversion Ratio Outstanding stock percent that should be acquired for rights to be exercised Minimum Outstanding Stock Percentage That Should Be Acquired For Rights Issued To Become Exercisable Minimum Outstanding Stock Percentage That Should be Acquired for Rights Issued to Become Exercisable Limited partnership units convertible into shares of common stock, eligible for conversion (in shares) Limited Partners Capital Account Convertible Units Eligible For Conversion Limited Partners' Capital Account, Convertible Units, Eligible for Conversion Fully converted partnership units and diluted weighted average shares outstanding (in shares) Partners Capital Account Units Converted And Weighted Average Shares Outstanding Diluted Partners' Capital Account, Units, Converted and Weighted Average Shares Outstanding, Diluted Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Business Segments Segment Reporting Disclosure [Text Block] Business Segments Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Name of Property [Axis] Name of Property [Axis] Name of Property [Domain] Name of Property [Domain] Washington Square Washington Square [Member] Washington Square [Member] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Forecast Scenario, Forecast [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] New Facility New Facility [Member] New Facility [Member] Burtonsville Fixed Rate Mortgage Burtonsville Fixed Rate Mortgage [Member] Burtonsville Fixed Rate Mortgage [Member] Glebe Road Construction Loan Glebe Road Construction Loan [Member] Glebe Road Construction Loan [Member] Park Van Ness Loan Park Van Ness Loan [Member] Park Van Ness Loan [Member] Washington Square 2017 Mortgage Washington Square 2017 Mortgage [Member] Washington Square 2017 Mortgage [Member] Kentlands Square II Bank Loan Kentlands Square II Bank Loan [Member] Kentlands Square II Bank Loan [Member] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Line Revolving Credit Facility [Member] Unsecured Revolving Credit Facility Unsecured Revolving Credit Facility [Member] Unsecured Revolving Credit Facility [Member] Letter of Credit Letter of Credit [Member] Term Loan Term Facility [Member] Term Facility [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] LIBOR London Interbank Offered Rate (LIBOR) [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Line of Credit [Member] Line of Credit [Member] 3.75% due December 2032 Three Point Seven Five Maturing December Twenty Thirty Two [Member] Three Point Seven Five Maturing December Twenty Thirty Two [Member] Fixed Rate Mortgage Notes Payable Fixed Rate Mortgage Notes Payable [Member] Fixed Rate Mortgage Notes Payable Debt Instrument [Line Items] Debt Instrument [Line Items] Outstanding debt Debt outstanding with fixed-rate Long-term Debt, Percentage Bearing Fixed Interest, Amount Debt outstanding with variable-rate Long-term Debt, Percentage Bearing Variable Interest, Amount Outstanding line of credit Long-term Line of Credit Carrying value of properties collateralizing mortgage notes SEC Schedule III, Real Estate, Gross Line of credit facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Line of credit facility, maximum borrowing capacity Line of Credit Facility, Remaining Borrowing Capacity Interest rate spread on LIBOR (percentage) Debt Instrument, Basis Spread on Variable Rate Debt instrument, term Debt Instrument, Term Construction-to-permanent loan Debt Instrument, Face Amount Interest rate, stated percentage Debt Instrument, Interest Rate, Stated Percentage Periodic payment Debt Instrument, Periodic Payment Amortization period Debt Instrument, Amortization Period Debt Instrument, Amortization Period Final payment amount Construction loan Secured Debt Principal amount Guarantor obligations, maximum exposure Guarantor Obligations, Maximum Exposure, Undiscounted Total outstanding debt Senior Notes Statement of Stockholders' Equity [Abstract] Dividends [Axis] Dividends [Axis] Dividends [Domain] Dividends [Domain] Dividend Distributions Payable Dividend Declared [Member] Issuance of Series D Cumulative preferred stock (in shares) Stock Issued During Period, Shares, New Issues Partial redemption of Series C Cumulative preferred stock (in shares) Stock Redeemed or Called During Period, Shares Shares pursuant to dividend reinvestment plan (in shares) Stock Issued During Period, Shares, Dividend Reinvestment Plan Shares due to exercise of employee stock options and issuance of directors' deferred stock (in shares) Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Issuance of partnership units pursuant to dividend reinvestment plan (in shares) Partnership Units Issued During Period Partnership Units Issued During Period Distributions payable on Series C preferred stock, per share (in usd per share) Preferred Stock, Dividends Per Share, Declared Distributions payable common stock, per share (in usd per share) Distributions partnership units, per unit (in usd per share) Distributions Per Limited Partnership Unit Outstanding, Basic Organization, Formation and Structure Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Subsequent Events [Abstract] Subsequent Events Subsequent Events [Text Block] Notes Payable, Revolving Credit Facility, Interest and Amortization of Deferred Debt Costs Debt Disclosure [Text Block] Nature of Operations Nature Of Operations Policy [Policy Text Block] Nature of Operations Principles of Consolidation Consolidation, Policy [Policy Text Block] Consolidation, Variable Interest Entity Consolidation, Variable Interest Entity, Policy [Policy Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Accounts Receivable, Accrued Income and Allowance for Doubtful Accounts Receivables, Policy [Policy Text Block] Assets Held for Sale Assets Held For Sale [Policy Text Block] Assets Held for Sale, Policy Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Construction In Progress Construction In Progress [Policy Text Block] Construction In Progress Deferred Debt Costs Debt, Policy [Policy Text Block] Deferred Income Deferred Revenue [Policy Text Block] Deferred Revenue, Policy Deferred Leasing Costs Deferred Charges, Policy [Policy Text Block] Derivative Financial Instruments Derivatives, Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Legal Contingencies Commitments and Contingencies, Policy [Policy Text Block] Postemployment Benefits Postemployment Benefit Plans, Policy [Policy Text Block] Predevelopment Expenses Pre Development Expense Policy [Policy Text Block] Pre-Development Expense Real Estate Investment Properties Real Estate, Policy [Policy Text Block] Revenue Recognition Revenue Recognition, Policy [Policy Text Block] Stock-based Employee Compensation, Stock Plan and Deferred Compensation Plan for Directors Compensation Related Costs, Policy [Policy Text Block] Noncontrolling Interests Noncontrolling Interests [Policy Text Block] Noncontrolling Interests, Policy Per Share Data Earnings Per Share, Policy [Policy Text Block] Recently Issued Accounting Standards New Accounting Pronouncements, Policy [Policy Text Block] Reclassifications Reclassification, Policy [Policy Text Block] Scheduled Maturities of Debt, Including Scheduled Principal Amortization Schedule of Maturities of Long-term Debt [Table Text Block] Interest Expense and Amortization of Deferred Debt Costs Schedule Of Interest Costs Incurred Table [Table Text Block] Schedule of Interest Costs Incurred Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Glebe Road Glebe Road [Member] Glebe Road [Member] Other Other Property [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Construction in progress Development in Process Company contribution to a multi employer 401K plan at discretionary amount of employee's cash compensation, maximum percentage Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent Company contribution to a multi employer 401K plan at discretionary amount of employee's cash compensation, amount Defined Contribution Plan, Employer Discretionary Contribution Amount Deferred compensation, employee contribution, percentage Deferred Compensation Arrangement With Individual Contributions By Plan Participants Percentage Of Salary Maximum Deferred Compensation Arrangement with Individual, Contributions by Plan Participants, Percentage of Salary, Maximum Deferred compensation, company contribution, amount Deferred Compensation Arrangement with Individual, Contributions by Employer Deferred compensation, company contribution, percentage Deferred Compensation Arrangement with Individual, Employer Contribution, Percentage Deferred Compensation Deferred Compensation Arrangement with Individual, Employer Contribution, Percentage Deferred Compensation Deferred compensation, cumulative unfunded liability Deferred Compensation Arrangement with Individual, Recorded Liability Ancillary costs and expenses Ancillary Costs And Expenses Ancillary Costs and Expenses Liability due to The Saul Organization for the Company's share of these ancillary costs and expenses Due to Related Parties Purchases from related party Related Party Transaction, Purchases from Related Party Area of real estate acquired (in acres) Related Party Transaction, Area of Real Estate Acquired Related Party Transaction, Area of Real Estate Acquired Percentage of annual increase in base rent Operating Leases Annual Increase In Rent Expense Operating Leases Annual Increase in Rent Expense Rent expense Operating Leases, Rent Expense, Net Insurance commissions and fees expense Operating Insurance and Claims Costs, Production Significant Accounting Policies [Table] Significant Accounting Policies [Table] Significant Accounting Policies [Table] Common Stock Common Stock [Member] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Revenues Sales Revenue, Services, Net [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Giant Food Giant Food [Member] Giant Food [Member] Capital One Capital One [Member] Capital One [Member] Held-for-sale Property Held-for-sale [Member] Property Held-for-sale [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Building Building [Member] Building Improvements Building Improvements [Member] Significant Accounting Policies [Line Items] Significant Accounting Policies [Line Items] Significant Accounting Policies [Line Items] Number of tenants Number Of Tenants Number of Tenants Number of shopping centers Number of Stores Percentage of total revenue Percentage Of Total Revenue Percentage of Total Revenue Number of shopping centers Number Of Shopping Centers Number Of Shopping Centers Percentage of ownership in operating partnership Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest Allowance for doubtful accounts receivables Allowance for Doubtful Accounts Receivable Accounts receivable, net representing rental income accrued Accrued Fees and Other Revenue Receivable Allowance for doubtful accounts receivables representing rental income accrued Allowance for Doubtful Accounts, Premiums and Other Receivables Period expected for the sale of property to occur Assets Held-for-sale, Period of Sale Assets Held-for-sale, Period of Sale Deferred debt costs Accumulated amortization, deferred debt costs Accumulated Amortization, Debt Issuance Costs Deferred leasing costs, net Deferred Costs, Leasing, Net Accumulated amortization deferred leasing cost Deferred Costs, Leasing, Accumulated Amortization Amortization expense deferred leasing cost Amortization of Deferred Leasing Fees Interest capitalized Commercial development projects, availability for occupancy, maximum period after major construction activity Commercial Development Projects, Availability for Occupancy after Construction, Maximum Period Commercial Development Projects, Availability for Occupancy after Construction, Maximum Period Estimated useful life (in years) Property, Plant and Equipment, Useful Life Depreciation expense Depreciation, Depletion and Amortization, Nonproduction Repairs and maintenance expense Cost of Property Repairs and Maintenance Shares credited to directors' deferred fee accounts (in shares) Deferred Compensation Arrangement with Individual, Shares Issued Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Leases, Acquired-in-Place Leases, Acquired-in-Place [Member] Below Market Leases Above Market Leases [Member] Below Market Leases Below Market Leases [Member] Below Market Leases [Member] Burtonsville Town Square Burtonsville Town Square [Member] Burtonsville Town Square [Member] Olney Olney [Member] Olney [Member] Great Eastern Shopping Center Great Eastern Shopping Center [Member] Great Eastern Shopping Center [Member] 7316 Wisconsin Avenue 7316 Wisconsin Avenue [Member] 7316 Wisconsin Avenue [Member] 7316 Wisconsin Avenue Retail Space 7316 Wisconsin Avenue Retail Space [Member] 7316 Wisconsin Avenue Retail Space [Member] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Group Name [Domain] Disposal Group Name [Domain] Business Acquisition [Line Items] Business Acquisition [Line Items] Payments to acquire real estate Number of properties purchased Number of Businesses Acquired Portion of purchase price allocated to land Land and Land Improvements Portion of purchase price allocated to buildings Buildings and Improvements, Gross Portion of purchase price allocated to leases acquired in place Real Estate Investments, Other Proceeds from sale of real estate Proceeds from Sale of Real Estate Second trust financing Mortgage Loans on Real Estate Second trust financing, stated interest rate Mortgage Loans on Real Estate, Interest Rate Optional extension period Mortgage Loan, Optional Extension Period Mortgage Loan, Optional Extension Period Gains (losses) on sales of investment real estate Gains (Losses) on Sales of Investment Real Estate Property acquisition costs Real Estate Inventory, Capitalized Interest Costs Earnest money deposits Payments for Deposits on Real Estate Acquisitions Number of units in real estate property Number of Units in Real Estate Property Area of real estate property (in square feet) Area of Real Estate Property Fair Value of Financial Instruments Fair Value Disclosures [Text Block] Changes in Fair Value of Derivatives Derivative Instruments, Gain (Loss) [Table Text Block] Number of stock option plans Number Of Stock Option Plans Number of Stock Option Plans Option expiration period Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Option vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Closing share price (in usd per share) Share Price Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] 2015 2015 [Member] 2015 [Member] 2016 2016 [Member] 2016 [Member] 2017 2017 [Member] 2017 [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Weighted average remaining contractual life of the Company's outstanding options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Weighted average remaining contractual life of the Company's exercisable options Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Total Saul Centers, Inc. Parent [Member] Preferred Stock Preferred Stock [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Accumulated Deficit Retained Earnings [Member] Accumulated Other Comprehensive (Loss) AOCI Attributable to Parent [Member] Dividend Paid Dividend Paid [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning Balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Issuance of 30,000 shares of Series D Cumulative preferred stock Stock Issued During Period, Value, New Issues Redemption of 30,000 shares of Series C Cumulative preferred stock Stock Redeemed or Called During Period, Value Issuance of common stock: Common Stock Transactions [Abstract] Common Stock Transactions [Abstract] 69,750 shares pursuant to dividend reinvestment plan Stock Issued During Period, Value, Dividend Reinvestment Plan 8,088 shares due to exercise of employee stock options and issuance of directors’ deferred shares Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Issuance of 38,037 partnership units pursuant to dividend reinvestment plan Partnership Units Issued During Period, Value Partnership Units Issued During Period, Value Net income Change in unrealized loss on cash flow hedge Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Net of Tax Preferred stock distributions Dividends, Preferred Stock, Cash Common stock distributions Dividends, Common Stock Ending Balance Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Outstanding at beginning of period (in shares) Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Exercised (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Expired/Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Outstanding at end of period (in shares) Exercisable at end of period (in shares) Weighted Average Exercise Price per share Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Outstanding at beginning of period (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (in usd per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised (in usd per share) Expired/Forfeited (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Outstanding at end of period (in usd per share) Exercisable at end of period (in usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Aggregate Intrinsic Value Share Based Compensation Arrangement By Share Based Payment Award Options Aggregate Intrinsic Value [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Roll Forward] Outstanding at beginning of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Granted Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Intrinsic Value Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Intrinsic Value Exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Expired/Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Intrinsic Value Outstanding at end of period Exercisable at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Change in fair value: Changes In Fair Value [Abstract] Changes in Fair Value [Abstract] Recognized in earnings Recognized in other comprehensive income Total change in fair value Increase Decrease In Fair Value Of Interest Rate Swaps Net Increase / (decrease) in fair value of interest rate swaps, net. Real Estate Transactions Real Estate Disclosure [Text Block] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Consolidation Items [Axis] Consolidation Items [Axis] Consolidation Items [Domain] Consolidation Items [Domain] Operating Segments Operating Segments [Member] Corporate and Other Corporate, Non-Segment [Member] Segments [Axis] Segments [Axis] Segments [Domain] Segments [Domain] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Real estate rental operations: Real Estate Revenue, Net [Abstract] Revenue Expenses Cost of Real Estate Revenue Income from real estate Gross Profit Interest expense and amortization of deferred debt costs General and administrative Subtotal Segment Reporting Information Operating Income Loss Before Depreciation And Amortization Segment Reporting Information, Operating Income (Loss) before Depreciation and Amortization Depreciation and amortization of deferred leasing costs Depreciation, Depletion and Amortization, Including Discontinued Operations Depreciation, Depletion and Amortization, Including Discontinued Operations Capital investment Payments to Acquire Productive Assets Total assets Assets Statement of Financial Position [Abstract] Assets Assets [Abstract] Real estate investments Real Estate Investments, Net [Abstract] Land Land Buildings and equipment Investment Building and Building Improvements Construction in progress Real estate investments Real Estate Investment Property, at Cost Accumulated depreciation Real Estate Investment Property, Accumulated Depreciation Real estate investments, net Real Estate Investment Property, Net Cash and cash equivalents Accounts receivable and accrued income, net Accounts and Notes Receivable, Net Deferred leasing costs, net Prepaid expenses, net Prepaid Expense Other assets Other Assets Total assets Liabilities Liabilities [Abstract] Notes payable Revolving credit facility payable Term loan facility payable Loans Payable Dividends and distributions payable Dividends Payable Accounts payable, accrued expenses and other liabilities Accounts Payable Accrued Expenses And Other Liabilities Accounts payable, accrued expenses and other liabilities Deferred income Deferred Revenue Total liabilities Liabilities Equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Preferred stock, 1,000,000 shares authorized: Series C Cumulative Redeemable, 72,000 shares issued and outstanding Preferred Stock, Value, Issued Common stock, $0.01 par value, 40,000,000 shares authorized, 22,200,966 and 22,123,128 shares issued and outstanding, respectively Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Accumulated deficit Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total Saul Centers, Inc. equity Stockholders' Equity Attributable to Parent Noncontrolling interest Stockholders' Equity Attributable to Noncontrolling Interest Total equity Total liabilities and equity Liabilities and Equity Properties Acquired, in Development and Disposed Schedule of Real Estate Properties [Table Text Block] Statement of Comprehensive Income [Abstract] Other comprehensive income Other Comprehensive Income (Loss), Net of Tax [Abstract] Total comprehensive income Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive income attributable to noncontrolling interests Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest Total comprehensive income attributable to Saul Centers, Inc. Comprehensive Income (Loss), Net of Tax, Attributable to Parent Preferred stock dividends Total comprehensive income attributable to common stockholders Total Comprehensive Income Loss Available To Common Stockholders Total Comprehensive Income (Loss) Available To Common Stockholders Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Stock Options Issued Share-based Compensation, Stock Options, Activity [Table Text Block] Summary of Option Activity Schedule of Stock Options Roll Forward [Table Text Block] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Cumulative redeemable preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Cumulative redeemable 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 Noncontrolling Interests - Holders of Convertible Limited Partnership Units in the Operating Partnership Noncontrolling Interest Disclosure [Text Block]