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[Member] Net Lease Strategic Assets Fund L.P. [Member] Net Lease Strategic Assets Fund L.P. 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Ventures, Maximum Construction Financing Real Estate Investments, Joint Ventures, Maximum Construction Financing Face amount Debt Instrument, Face Amount Investment advisory fees Investment Advisory Fees Payments to acquire equity method investments Payments to Acquire Equity Method Investments Ownership percentage Cost Method Investment, Ownership Percentage Cost Method Investment, Ownership Percentage Payments to acquire real estate Payments to Acquire Real Estate Held-for-investment Units issued (in shares) Limited Partners' Capital Account, Units Issued Equity method investments Equity Method Investments Equity in earnings (losses) of non-consolidated entities Income (Loss) from Equity Method Investments Contributions to equity method investment Contributions to Equity Method Investment Contributions to Equity Method Investment Proceeds from dividends received Proceeds from Dividends Received Debt Disclosure [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Debt Instrument [Line Items] Debt Instrument [Line Items] Mortgages and Notes Payable Long-term Debt [Text Block] Disclosure of Compensation Related Costs, Share-based Payments [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] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Share-based Compensation Award, Tranche One [Member] Share-based Compensation Award, Tranche One [Member] Share-based Compensation Award, Tranche Two [Member] Share-based Compensation Award, Tranche Two [Member] Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Index Performance Shares [Member] Index Performance Shares [Member] Index Performance Shares [Member] Peer Performance Shares [Member] Peer Performance Shares [Member] Peer Performance Shares [Member] Non-vested Shares [Member] Non-vested Shares [Member] Non-vested Shares [Member] Performance Shares [Member] Performance Shares [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Shares issued for services (in shares) Stock Issued During Period, Shares, Issued for Services Value per share granted (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Shares issued for services, value Stock Issued During Period, Value, Issued for Services Measurement period (in years) Share-based Compensation Arrangement by Share-based Payment Award, Measurement Period Share-based Compensation Arrangement by Share-based Payment Award, Measurement Period Vesting period (in years) Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Mortgages, Notes Payable, Credit Facility Borrowings, and Term Loans [Member] Mortgages, Notes Payable, Credit Facility Borrowings, and Term Loans [Member] Mortgages, Notes Payable, Credit Facility Borrowings, and Term Loans [Member] Mortgages, Notes Payable, and Co-borrower Debt [Member] Mortgages, Notes Payable, and Co-borrower Debt [Member] Mortgages, Notes Payable, and Co-borrower Debt [Member] 2018 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 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 Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Long-term debt, gross Long-term Debt, Gross Unamortized discount Debt Instrument, Unamortized Discount Unamortized debt issuance costs Debt Issuance Costs, Net Long-term debt Long-term Debt Document and Entity Information [Abstract] Document and Entity Information [Abstract] Entities [Table] Entities [Table] Entity Information [Line Items] Entity Information [Line Items] 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 User Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding (in shares) Entity Common Stock, Shares Outstanding Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Document Type Document Type Amendment Flag Amendment Flag Document Period Ended Date 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carrying value to their fair value and the allowance expensed for the period based on estimated losses to be realized from loan transactions. Gains on sales of properties Gain (Loss) on Sale of Properties, before Applicable Income Taxes Income (loss) before provision for income taxes and equity in earnings of non-consolidated entities Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Provision for income taxes Income Tax Expense (Benefit) Income (loss) from continuing operations Income (Loss) from Continuing Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Discontinued operations: Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Income from discontinued operations Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax Provision for income taxes Discontinued Operation, Tax Effect of Discontinued Operation Gains on sales of properties Discontinued Operation, Gain (Loss) on Disposal of Discontinued Operation, Net of Tax Total 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[Abstract] Income from continuing operations Income Loss From Continuing Operations Attributable To Common Shareholders Income Loss From Continuing Operations Attributable To Common Shareholders Income from discontinued operations Income Loss From Discontinued Operations Net Of Tax Attributable To Common Shareholders Income Loss From Discontinued Operations Net Of Tax Attributable To Common Shareholders Net income (loss) (usd per unit) Net Income (Loss), Per Outstanding Limited Partnership and General Partnership Unit, Basic and Diluted, Net of Tax Weighted-average units outstanding (in units) Weighted Average Number of Limited Partnership and General Partnership Unit Outstanding, Basic and Diluted Discontinued Operations and Disposal Groups [Abstract] Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Property Dispositions and Real Estate Impairment Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Risks and Uncertainties [Abstract] Concentration Risk [Table] Concentration Risk [Table] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Tenant Concentration Risk [Member] Tenant Concentraion Risk [Member] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] SM Ascott LLC [Member] SM Ascott LLC [Member] SM Ascott LLC [Member] Tribeca Ascott LLC [Member] Tribeca Ascott LLC [Member] Tribeca Ascott LLC [Member] AL Stone Ground Tenant LLC [Member] AL Stone Ground Tenant LLC [Member] AL Stone Ground Tenant LLC [Member] Preferred Freezer Services of Richland, LLC [Member] Preferred Freezer Services of Richland, LLC [Member] Preferred Freezer Services of Richland, LLC [Member] Hotel [Member] Hotel [Member] Concentration Risk [Line Items] Concentration risk percentage Concentration Risk, Percentage Lease term (in years) Lessee, Operating Lease, Term of Contract Number of properties Number of Real Estate Properties Real Estate Investments, Net [Abstract] Investments in Real Estate and Real Estate Under Construction [Table] Investments in Real Estate and Real Estate Under Construction [Table] Investments in Real Estate and Real Estate Under Construction [Table] Investments in Real Estate and Real Estate Under Construction [Line Items] Investments in Real Estate and Real Estate Under Construction [Line Items] Investments in Real Estate and Real Estate Under Construction [Line Items] Investments in Real Estate and Real Estate Under Construction Real Estate Disclosure [Text Block] SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Abstract] Real Estate and Accumulated Depreciation, by Property [Table] SEC Schedule III, Real Estate and Accumulated Depreciation, by Property [Table] Real Estate and Accumulated Depreciation [Line Items] SEC Schedule III, Real Estate and Accumulated Depreciation [Line Items] Real Estate and Accumulated Depreciation Disclosure SEC Schedule III, Real Estate and Accumulated Depreciation Disclosure [Text Block] Earnings Per Share [Abstract] Schedule of Earnings Per Share Reconciliation Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] BASIC Income from continuing operations attributable to common shareholders Income from discontinued operations attributable to common shareholders DILUTED: Impact of assumed conversions Dilutive Securities, Effect on Basic Earnings Per Share, Options and Restrictive Stock Units Income from continuing operations attributable to common shareholders Loss From Continuing Operations Attributable to Common Shareholders Net of Deductions Loss From Continuing Operations Attributable to Common Shareholders Net of Deductions Impact of assumed conversions: Incremental Common Shares Attributable To Operating Partnership Units Discontinued Operations Incremental Common Shares Attributable To Operating Partnership Units Discontinued Operations Income from discontinued operations attributable to common shareholders Income (Loss) From Discontinued Operations Attributable To Common Shareholders, Net Of Deductions Income (Loss) From Discontinued Operations Attributable To Common Shareholders, Net Of Deductions Net income attributable to common shareholders Net Income (Loss) Available to Common Stockholders, Diluted Effect of dilutive securities: Incremental Weighted Average Shares Attributable to Dilutive Effect [Abstract] Share options (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Operating Partnership Units (in units) Incremental Common Shares Attributable to Operating Partnership Units Incremental Common Shares Attributable to Operating Partnership Units Weighted-average common shares outstanding (in shares) Mortgages and Notes Payable [Member] Mortgages and Notes Payable [Member] Mortgages and Notes Payable [Member] Mortgages and notes payable Accounting Policies [Abstract] Schedule of Variable Interest Entities Schedule of Variable Interest Entities [Table Text Block] Related Party Transactions [Abstract] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Related Party Transactions Related Party Transactions Disclosure [Text Block] Income Tax Disclosure [Abstract] Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State and local Current State and Local Tax Expense (Benefit) NOL utilized Current Net Operating Loss Utilized Current Net Operating Loss Utilized Deferred: Deferred Income Taxes and Other Assets [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State and local Deferred State and Local Income Tax Expense (Benefit) Benefit (provision) for income taxes Real Estate [Abstract] Variable Interest Entities [Axis] Variable Interest Entities [Axis] Variable Interest Entity, Classification [Domain] Variable Interest Entity, Classification [Domain] Development Deals [Member] Development Deals [Member] Development Deals [Member] Below-market leases, net of accretion Below Market Lease, Net Future accretion, year 1 Below Market Lease, Amortization Income, Next Twelve Months Future accretion, year 2 Below Market Lease, Amortization Income, Year Two Future accretion, year 3 Below Market Lease, Amortization Income, Year Three Future accretion, year 4 Below Market Lease, Amortization Income, Year Four Future accretion, year 5 Below Market Lease, Amortization Income, Year Five Acquisition related costs Business Combination, Acquisition Related Costs Construction in progress Construction in Progress, Gross Interest costs capitalized Interest Costs Capitalized Change in amount of contingent consideration Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Schedule of Accounts, Notes, Loans and Financing Receivable [Table] Convertible Debt [Member] Convertible Debt [Member] 6.804% Trust Preferred Securities [Member] Six Point Eight Zero Four Percent Trust Preferred Securities [Member] Six Point Eight Zero Four Percent Trust Preferred Securities [Member] Senior Notes [Member] Senior Notes [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Six Percent Convertible Guaranteed Note [Member] Six Percent Convertible Guaranteed Note [Member] 6.00% Convertible Guaranteed Note [Member] Senior Notes Due 2024 [Member] Senior Notes Due 2024 [Member] Senior Notes Due 2024 [Member] Senior Notes Due 2023 [Member] Senior Notes Due 2023 [Member] Senior Notes Due 2023 [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] London Interbank Offered Rate (LIBOR) [Member] London Interbank Offered Rate (LIBOR) [Member] Accounts, Notes, Loans and Financing Receivable [Line Items] Accounts, Notes, Loans and Financing Receivable [Line Items] Debt interest rate percentage Debt Instrument, Interest Rate, Stated Percentage Original debt, amount Debt Conversion, Original Debt, Amount Shares issued (in shares) Debt Conversion, Converted Instrument, Shares Issued Cash payments Debt Conversion, Converted Instrument, Cash Payments Debt Conversion, Converted Instrument, Cash Payments Debt satisfaction (gains) charges, net Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Effective interest percentage Debt Instrument, Interest Rate, Effective Percentage Principal amount outstanding on Trust Preferred Securities Principal Amount Outstanding on Loans Securitized or Asset-backed Financing Arrangement Debt issuance costs, gross Debt Issuance Costs, Gross Long-term debt Leases [Abstract] Schedule of Operating Leased Assets [Table] Schedule of Operating Leased Assets [Table] Operating Leased Assets [Line Items] Operating Leased Assets [Line Items] Schedule of Future Minimum Rental Payments Receivable for Operating Leases Schedule of Future Minimum Rental Payments Receivable for Operating Leases [Table Text Block] Schedule of Future Minimum Rental Payments Receivable for Operating Leases [Table Text Block] Schedule of Future Minimum Rental Payments for Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Concentration Risk [Line Items] Schedules of Concentration of Risk, by Risk Factor Schedules of Concentration of Risk, by Risk Factor [Table Text Block] Schedule of Components of Income Tax Expense (Benefit) Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Statutory Accounting 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Percent of Principal Balance Loans Receivable, Sold During Period, Percent of Principal Balance Gain (loss) on sales of loans, net Gain (Loss) on Sales of Loans, Net Professional fees Professional Fees Commitments and Contingencies Disclosure [Abstract] Loss Contingencies [Table] Loss Contingencies [Table] Litigation Case [Axis] Litigation Case [Axis] Litigation Case [Domain] Litigation Case [Domain] Bridgewater Hills Corporate Center, LLC [Member] Bridgewater Hills Corporate Center, LLC [Member] Bridgewater Hills Corporate Center, LLC [Member] Range [Axis] Range [Domain] Maximum [Member] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Axis] Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Financial Guarantee [Member] Financial Guarantee [Member] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event [Member] Subsequent Event [Member] Loss Contingencies 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Liabilities Debt, Carrying Amount Debt, Long-term and Short-term, Combined Amount Debt, Fair Value Debt Instrument, Fair Value Disclosure Subsequent Events [Abstract] Subsequent Events Subsequent Events [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Schedule of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Limited partners, ownership interest Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest Number of consolidated properties Number of states in which entity has interests Number of States in which Entity Operates Minimum [Member] Unsecured Credit Agreement [Member] Unsecured Credit Agreement [Member] Unsecured Credit Agreement [Member] Unsecured Debt [Member] Unsecured Debt [Member] Weighted-average interest rate Debt, Weighted Average Interest Rate Line of credit facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Line of credit facility, maximum borrowing capacity with lender approval Line of Credit Facility, Maximum Borrowing Capacity with Lender Approval Line of Credit Facility, Maximum Borrowing Capacity with Lender Approval Debt satisfaction gains (charges), net Interest paid, capitalized Interest Costs Capitalized Adjustment Co-borrower debt Obligation with Joint and Several Liability Arrangement, Amount Recognized The Company/Partnership Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Options 2010 [Member] Options 2009 [Member] Options 2008 [Member] Non-Management Award Grant [Member] Non-Management Award Grant [Member] Non-Management Award Grant [Member] Shares Subject to Time [Member] Shares Subject to Time 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Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period After Termination Number of trading period days (in days) Number Of Trading Period Days Where Entity's Average Closing Price Per Common Share Is Greater Than The Stated Lower Amount Triggering Vesting Number Of Trading Period Days Where Entity's Average Closing Price Per Common Share Is Greater Than The Stated Lower Amount Triggering Vesting Average closing price, lower limit (usd per share) Stated Lower Amount Where Entity's Average Closing Price Per Common Share Is Greater Than The Stated Amount Triggering Stated Lower Amount Where Entity's Average Closing Price Per Common Share Is Greater Than The Stated Amount Triggering Vesting Options convertible to common shares Share Based Compensation Arrangement by Share Based Payment Award Options Convertible To Common Shares Share Based Compensation Arrangement by Share Based Payment Award Options Convertible To Common Shares Options converted to common 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