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Washington, D.C. Segment [Member] Washington, D.C. Segment Atlanta Atlanta Segment [Member] Atlanta Segment Boston Boston Segment [Member] Boston Segment Los Angeles Los Angeles Segment [Member] Los Angeles Segment All other office markets All Other Markets Segment [Member] All Other Markets Segment Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Operating revenues including unconsolidated joint venture Revenues, Including Unconsolidated Joint Venture Revenues, Including Unconsolidated Joint Venture Ownership percentage Equity Method Investment, Ownership Percentage Operating revenues Revenues Management fee income Leases [Abstract] Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Ground Leases Land [Member] Office Lease Building [Member] Lessee, Lease, Description [Line Items] Lessee, Lease, Description 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Management Service [Member] Other property income Real Estate, Other [Member] Statement [Line Items] Statement [Line Items] Revenues: Revenues [Abstract] Lease revenues Operating Lease, Lease Income Lease revenues Operating Leases, Income Statement, Lease Revenue Revenues Revenue from Contract with Customer, Excluding Assessed Tax Revenues Expenses: Operating Expenses [Abstract] Cost of goods and services sold Cost of Goods and Services Sold Depreciation Depreciation Amortization Amortization Impairment loss on real estate assets Impairment of Real Estate General and administrative – corporate General and Administrative Expense, Corporate General and Administrative Expense, Corporate General and administrative – unconsolidated joint ventures General and Administrative Expense, Unconsolidated Joint Venture General and Administrative Expense, Unconsolidated Joint Venture Costs and expenses Operating Expenses Other Income (Expense): Nonoperating Income (Expense) [Abstract] Interest expense Interest Expense Gain on extinguishment of debt Gain (Loss) on Extinguishment of Debt Interest and other income Interest and Other Income Gain on sale of unconsolidated joint venture interests Equity Method Investment, Realized Gain (Loss) on Disposal Income tax expense Income Tax Expense (Benefit) Income from unconsolidated joint ventures Income (Loss) from Equity Method Investments, Joint Ventures Income (Loss) from Equity Method Investments, Joint Ventures Gain on sale of real estate assets Gain (Loss) on Sale of Properties, Net of Applicable Income Taxes Nonoperating income (expense) Nonoperating Income (Expense) Net income (loss) Net Income (Loss) Attributable to Parent Per-Share Information – Basic: Earnings Per Share, Basic [Abstract] Net income (loss) (dollars per share) Earnings Per Share, Basic Weighted-average common shares outstanding – basic Weighted Average Number of Shares Outstanding, Basic Per-Share Information – Diluted: Earnings Per Share, Diluted [Abstract] 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[Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Estimated useful life of real estate assets Property, Plant and Equipment, Useful Life Fair value of real estate investment Real Estate Investment, Fair Value Disclosure Real Estate Investment, Fair Value Disclosure Intangible lease assets, gross Finite-Lived Intangible Assets, Gross Intangible lease assets, accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Hedge ineffectiveness recognized in earnings Gain (Loss) on Interest Rate Fair Value Hedge Ineffectiveness Requirement to distribute taxable income (at least) Requirement to Distribute Taxable Income, Percent Requirement to Distribute Taxable Income, Percent Limit on investments in taxable real estate investment trusts (percent) Limit on Investments in Taxable Real Estate Investment Trusts, Percent Limit on Investments in Taxable Real Estate Investment Trusts, Percent Schedule of Share-based Compensation 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respectively Off-market Lease, Unfavorable Total liabilities Liabilities Commitments and Contingencies (Note 7) Commitments and Contingencies Equity: Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract] Common stock, $0.01 par value, 225,000,000 shares authorized, 116,908,658 and 116,698,033 shares issued and outstanding, as of June 30, 2019 and December 31, 2018, respectively Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital, Common Stock Cumulative distributions in excess of earnings Accumulated Distributions in Excess of Net Income Cumulative other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Total equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total liabilities and equity Liabilities and Equity Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Property 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Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Revenues Business Acquisition, Pro Forma Revenue Net income Business Acquisition, Pro Forma Net Income (Loss) Summary of Significant Accounting Policies Basis of Presentation and Significant Accounting Policies [Text Block] Fixed payments Operating Lease, Fixed Lease Income Operating Lease, Fixed Lease Income Variable payments Operating Lease, Variable Lease Income Total lease revenues Schedule of Future Minimum Lease Payments To Be Made Lessee, Operating Lease, Liability, Maturity [Table Text Block] Schedule of Future Minimum Lease Payments to be Made and Received Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Summary of Impact of Operating Leases on Consolidated Balance Sheet Assets And Liabilities, Lessee [Table Text Block] Assets And Liabilities, Lessee [Table Text Block] Summary of Impact of Operating Leases on Statements of Operations and Statements of Cash Flows Lease, Cost [Table Text Block] Summary of Fixed and Variable Revenues Operating Lease, Lease Income [Table Text Block] Schedule of Future Minimum Lease Payments To Be Received Lessor, Operating Lease, Payments to be Received, Maturity [Table Text Block] Title of Individual [Axis] Title of Individual [Axis] Title of Individual [Domain] Title of Individual [Domain] Director Director [Member] Award Date [Axis] Award Date [Axis] Award Date [Domain] Award Date [Domain] May 14, 2019 May 14, 2019 [Member] May 14, 2019 [Member] May 14, 2018 May 14, 2018 [Member] May 14, 2018 [Member] Shares granted Grant-Date Fair Value (dollars 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 Subsequent Events [Abstract] Subsequent Events Subsequent Events [Text Block] 799 Broadway Ownership Interest Purchase Price Purchase Price Earnings Per Share Earnings Per Share [Text 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of Business Acquisitions, by Acquisition [Table Text Block] Unaudited Pro Forma Financial Results Business Acquisition, Pro Forma Information [Table Text Block] Schedule of Properties Sold Disposal Groups, Including Discontinued Operations [Table Text Block] Schedule of Finite-Lived Intangible Assets by Major Class Schedule of Finite-Lived Intangible Assets [Table] Above-Market In-Place Lease Assets Above-Market In-Place Lease Assets [Member] Above-Market In-Place Lease Assets [Member] Absorption Period Costs Absorption Period Costs [Member] Absorption Period Costs [Member] Intangible Lease Origination Costs Intangible Lease Origination Costs [Member] Intangible Lease Origination Costs [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Gross Intangible In-Place Lease Assets and Liabilities [Abstract] Gross Intangible In-Place Lease Assets and Liabilities [Abstract] Gross Intangible In-Place Lease Assets and Liabilities [Abstract] Intangible Lease Assets, Gross Intangible Lease Assets, Accumulated Amortization Intangible lease assets, net Intangible Lease Origination Costs, Gross Finite-Lived Intangible Asset, Acquired-in-Place Leases, Gross Finite-Lived Intangible Asset, Acquired-in-Place Leases, Gross Intangible Lease Origination Costs, Accumulated Amortization Finite Lived Intangible Assets, Acquired in Place leases, Accumulated Amortization The accumulated amount of amortization of finite-lived intangible assets for acquired in-place leases. 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Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net Non-Lease Revenues Revenue from Contract with Customer [Text Block] Real Estate Transactions Real Estate Disclosure [Text Block] Schedule of Estimated Useful Lives for Real Estate Assets Schedule of Estimated Useful Lives for Real Estate Assets [Table Text Block] Schedule of Estimated Useful Lives for Real Estate Assets [Table Text Block] Schedule of Intangible Assets and Liabilities Schedule of Intangible Assets and Liabilities [Table Text Block] Schedule of Intangible Assets and Liabilities [Table Text Block] Schedule of Interest Rate Swaps Schedule of Interest Rate Derivatives [Table Text Block] Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location [Table Text Block] Equity Method Investments and Joint Ventures [Abstract] Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] University Circle Joint Venture University Circle Joint Venture [Member] University Circle Joint Venture [Member] 333 Market Street Joint Venture Three Thirty-Three Market Street Joint Venture [Member] Three Thirty-Three Market Street Joint Venture [Member] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Total Revenues Equity Method Investment, Summarized Financial Information, Revenue Net Income (Loss) Equity Method Investment, Summarized Financial Information, Net Income (Loss) Columbia Property Trust's Share of Net Income (Loss) Carrying Value of Investment Equity Method Investments Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Prepaid expenses and other assets 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Operating Leases [Text Block] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Employees Employees [Member] Employees [Member] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Stock-based compensation expense Share-based Payment Arrangement, Noncash Expense Future employee awards Deferred Compensation Arrangement with Individual, Compensation Expense Bonds Payable Unsecured Debt [Member] 2026 and 2025 Bonds Payable Two-Thousand and Twenty-Six and Two-Thousand and Twenty-Five Bonds Payable [Member] Two-Thousand and Twenty-Six and Two-Thousand and Twenty-Five Bonds Payable [Member] 2026 Bonds Payable Two-Thousand and Twenty-Six Bonds Payable [Member] Two-Thousand and Twenty-Six Bonds Payable [Member] 2025 Bonds Payable Two-Thousand and Twenty-Five Bonds Payable [Member] Two-Thousand 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improvements and rent abatements Payments For Tenant Improvements And Rent Abatements Payments For Tenant Improvements And Rent Abatements Repayment of debt Repayments of Debt Extinguishment of loan principal Extinguishment of Debt, Amount Interests sold Buildings and improvements, net Intangible lease assets, net Construction in progress Investment in subsidiaries Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Tenant receivables Intangible lease origination costs, net Deferred lease costs, net Lines of credit and notes payable, net Due to affiliates Due to Related Parties Intangible lease liabilities, net Total equity Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] ASU 2017-05 Accounting Standards Update 2017-05 [Member] ASU 2014-09 Accounting Standards Update 2014-09 [Member] Additional Paid-In Capital Additional Paid-in Capital [Member] Cumulative Distributions in Excess of Earnings Accumulated Distributions in Excess of Net Income [Member] Cumulative Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning balance, shares Common Stock, Shares, Outstanding Beginning balance, value Cumulative-effect adjustment for the adoption of ASU Cumulative Effect of New Accounting Principle in Period of Adoption Repurchases of common stock, shares Stock Repurchased and Retired During Period, Shares Repurchases of common stock Stock Repurchased and Retired During Period, Value Common stock issued to employees and directors, and amortized (net of income tax withholdings), shares Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Common stock issued to employees and directors, and amortized (net of income tax withholdings) Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Distributions to common stockholders ($0.20 in three months ended 2019 and 2018, $0.40 in 6 months ended 2019 and 2018) Dividends Ending balance, shares Ending balance, value Supplemental Cash Flow Elements [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] ASU 2017-05 Accounting Standards Update 2017-05 And 2014-09 [Member] Accounting Standards Update 2017-05 And 2014-09 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] Extinguishment of 263 Shuman Boulevard mortgage note by transferring property to lender Notes Reduction Amortization of net discounts on debt Amortization of Debt Discount (Premium) Accrued transaction costs Other Significant Noncash Transactions, Accrued Real Estate Transaction Costs Other Significant Noncash Transactions, Accrued Real Estate Transaction Costs Accrued investments in unconsolidated joint ventures Accrued Investments In Unconsolidated Joint Ventures Accrued Investments In Unconsolidated Joint Ventures Accrued capital expenditures and deferred lease costs Other Significant Noncash Transactions, Capital Expenditures Incurred but Not yet Paid and Deferred Leasing Costs, Noncash Other Significant Noncash Transactions, Capital Expenditures Incurred but Not yet Paid and Deferred Leasing Costs, Noncash Operating lease liability recorded at adoption of ASC 842 Lease Obligations Incurred, Operating Lease Lease Obligations Incurred, Operating Lease Cumulative-effect adjustment to equity for the adoption of ASU 2017-05 and ASU 2014-09 Amortization of common stock issued to employees and directors Common Stock Issued, Value Common Stock Issued, Value Schedule of Line of Credit and Notes Payable Indebtedness Schedule of Debt [Table Text Block] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Building and improvements, accumulated depreciation Real Estate Investment Property, Accumulated Depreciation Intangible lease assets, accumulated amortization Allowance for doubtful accounts Accounts Receivable, Allowance for Credit Loss Intangible lease origination costs, accumulated amortization Deferred lease costs, accumulated amortization Deferred Costs, Leasing, Accumulated Amortization Deferred financing costs, net Debt Issuance Costs, Net Bonds payable discount Debt Instrument, Unamortized Discount Intangible lease liabilities, accumulated amortization Off market lease, unfavorable, Accumulated Amortization The accumulated amount of amortization of off-market leases, unfavorable. Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued Common stock, shares outstanding Remainder of 2019 Lessor, Operating Lease, Payments to be Received, Remainder of Fiscal Year 2020 Lessor, Operating Lease, Payments to be Received, Two Years 2021 Lessor, Operating Lease, Payments to be Received, Three Years 2022 Lessor, Operating Lease, Payments to be Received, Four Years 2023 Lessor, Operating Lease, Payments to be Received, Five Years 2024 Lessor, Operating Lease, Payments to be Received, Six Years Lessor, Operating Lease, Payments to be Received, Six Years Thereafter Lessor, Operating Lease, Payments to be Received, After Year Six Lessor, Operating Lease, Payments to be Received, After Year Six Total Lessor, Operating Lease, Payments to be Received 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 Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Previously granted awards, unvested Future period LTI Plan awards 2015 Long Term Incentive Plan [Member] 2015 Long Term Incentive Plan [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Distributions paid on unvested shares Preferred Stock Dividends and Other Adjustments Net income (loss) used to calculate basic and diluted earnings per share Net Income (Loss) Available to Common Stockholders, Basic Weighted-average common shares – basic Plus incremental weighted-average shares from time-vested conversions, less assumed stock repurchases Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Weighted-average common shares – diluted Blackstone Property Partners Blackstone Property Partners [Member] Blackstone Property Partners [Member] Market Square, University Circle, 333 Market Street, 114 Fifth Avenue, 1800 M Street And 799 Broadway Joint Ventures Market Square, University Circle, 333 Market Street, 114 Fifth Avenue, 1800 M Street And 799 Broadway Joint Ventures [Member] Market Square, University Circle, 333 Market Street, 114 Fifth Avenue, 1800 M Street And 799 Broadway Joint Ventures [Member] Total Assets Equity Method Investment, Summarized Financial Information, Assets Total Debt Equity Method Investment, Summarized Financial Information, Liabilities Total Equity Equity Method Investment Summarized Financial Information, Equity Aggregate basis difference Equity Method Investment, Difference Between Carrying Amount and Underlying Equity Debt Real Estate Investments, Joint Ventures, Debt Real Estate Investments, Joint Ventures, Debt Mortgage note interest rate LIBOR (maximum) Debt Instrument, LIBOR, Maximum Debt Instrument, LIBOR, Maximum Number of extensions available Debt Instrument, Number Of Extensions Debt Instrument, Number Of Extensions Extension term Debt Instrument, Extension Term Debt Instrument, Extension Term Supplemental Disclosures of Noncash Investing and Financing Activities Cash Flow, Supplemental Disclosures [Text Block] Bonds Payable Bond Disclosure [Text Block] The entire disclosure for information about bonds, including repayment terms, interest rates, collateral provided, whether or not in compliance with covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with covenants. [Text Block] For the remainder of 2019 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year For the Years Ending December 31: Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract] 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 2024 Finite-Lived Intangible Assets, Amortization Expense, Year Six Finite-Lived Intangible Assets, Amortization Expense, Year Six Thereafter Finite-Lived Intangible Assets, Amortization Expense, after Year Six Finite-Lived Intangible Assets, Amortization Expense, after Year Six Intangible Below-Market In-Place Lease Liabilities Below Market Lease [Abstract] For the remainder of 2019 Below Market Lease, Amortization Income, Remainder of Fiscal Year For the years ending December 31: Below Market Lease, Net, Amortization Income, Fiscal Year Maturity [Abstract] 2020 Below Market Lease, Amortization Income, Year Two 2021 Below Market Lease, Amortization Income, Year Three 2022 Below Market Lease, Amortization Income, Year Four 2023 Below Market Lease, Amortization Income, Year Five 2024 Below Market Lease, Amortization Income, Year Six Below Market Lease, Amortization Income, Year Six Thereafter Below Market Lease, Amortization Income, after Year Six Below Market Lease, Amortization Income, after Year Six Segment Reconciling Items Segment Reconciling Items [Member] Amortization Adjustment For Amortization Continuing Operations The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives for continuing operations Net interest expense Interest Income (Expense), Net Interest income from development authority bonds Interest Income, Development Authority Bonds Interest Income, Development Authority Bonds Gain on sale of unconsolidated joint venture interests Gain on extinguishment of debt Income tax expense Adjustments included in income from unconsolidated joint ventures Income (Loss) from Equity Method Investments, Adjustment Income (Loss) from Equity Method Investments, Adjustment Gain on sale of real estate assets Impairment loss NOI Net Operating Income (Loss) Net Operating Income (Loss) Cover page. Document Type Document Type Document Quarterly Report Document Quarterly Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Restricted Stock [Member] Restricted Stock [Member] Shares Rollforward Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Unvested awards - beginning of period (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Vested (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Unvested awards - end of period (shares) Weighted-Average, Grant-Date Fair Value Rollforward Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Unvested awards - beginning of period (dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted (dollars per share) Vested (dollars 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 Unvested awards - end of period (dollars per share) Shares expected to ultimately vest Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expected to Vest Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expected to Vest Expected forfeiture rate Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expected Forfeiture Rate Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Expected Forfeiture Rate Operating Leases, Future Minimum Payments Due Lessee, Operating Lease, Liability, Payment, Due [Abstract] Remainder of 2019 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2020 Lessee, Operating Lease, Liability, Payments, Due Year Two 2021 Lessee, Operating Lease, Liability, Payments, Due Year Three 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four 2023 Lessee, Operating Lease, Liability, Payments, Due Year Five 2024 Lessee, Operating Lease, Liability, Payments, Due Year Six Lessee, Operating Lease, Liability, Payments, Due Year Six Thereafter Lessee, Operating Lease, Liability, Payments, Due After Year Six Lessee, Operating Lease, Liability, Payments, Due After Year Six Total lease payments Lessee, Operating Lease, Liability, Payments, Due Less: interest expense Lessee, Operating Lease, Liability, Undiscounted Excess Amount Present value of lease liabilities Weighted-average remaining lease term (years) Operating Lease, Weighted Average Remaining Lease Term Weighted-average discount rate Operating Lease, Weighted Average Discount Rate, Percent Operating Leases, Future Minimum Payments Due Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] 2019 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2020 Operating Leases, Future Minimum Payments, Due in Two Years 2021 Operating Leases, Future Minimum Payments, Due in Three Years 2022 Operating Leases, Future Minimum Payments, Due in Four Years 2023 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total Operating Leases, Future Minimum Payments Due Significant Noncash Investing and Financing Activities Schedule of Other Significant Noncash Transactions [Table Text Block] Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Hotel Net operating income (loss) including unconsolidated joint venture Net Operating Income (Loss) Including Unconsolidated Joint Venture Net Operating Income (Loss) Including Unconsolidated Joint Venture Amortization of Intangible Lease Assets Intangible Below-Market In-Place Lease Liabilities Amortization of Below Market Lease Statement of Comprehensive Income [Abstract] Reconciliation of Revenue from Segments to Consolidated Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Schedule of Segment Reporting Information, by Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Less: Deferred financing costs related to term loans and notes payable, net of accumulated amortization Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract Type [Domain] Derivative Contract [Domain] Interest rate contracts Interest Rate Contract [Member] Accounts payable Accounts Payable [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Derivative, Fair Value, Net [Abstract] Derivative, Fair Value, Net [Abstract] Derivative designated as hedging instruments Derivative Instruments in Hedges, at Fair Value, Net Summary of Derivative Instruments Impact on Results of Operations [Abstract] Summary of Derivative Instruments Impact on Results of Operations [Abstract] Market value adjustment to interest rate swaps designated as hedging instruments and included in other comprehensive income Interest expense Gain (loss) on extinguishment of debt Cash paid for operating lease liabilities in cash flows from operations Financial Information for Parent Guarantor, Issuer Subsidiary, and Non-Guarantor Subsidiaries Financial Information For Parent Issuer Guarantor Subsidiaries And Nonguarantor Subsidiaries [Text Block] Financial information for parent, issuer, guarantor subsidiaries, and nonguarantor subsidiaries. [Text Block] Unconsolidated Joint Ventures Equity Method Investments and Joint Ventures Disclosure [Text Block] Schedule of Real Estate Properties [Table] Schedule of Real Estate Properties [Table] Real Estate Property Ownership [Axis] Real Estate Property Ownership [Axis] Real Estate Properties [Domain] Real Estate Properties [Domain] Wholly Owned Properties Wholly Owned Properties [Member] Unconsolidated Properties Unconsolidated Properties [Member] Real Estate Properties [Line Items] Real Estate Properties [Line Items] Number of real estate properties Number of Real Estate Properties Number of properties under development Number Of Real Estate Properties Under Development Number Of Real Estate Properties Under Development Percent of leased office space of owned properties Leased Office Space of Owned Properties, Percent Leased Office Space of Owned Properties, Percent Operating lease, number of ground leases Lessee, Operating Lease, Number Of Contracts Lessee, Operating Lease, Number Of Contracts Lessee, operating lease, right-of-use asset, term of contract Lessee, Operating Lease, Right-of-Use Asset, Remaining Term Of Contract Lessee, Operating Lease, Right-of-Use Asset, Remaining Term Of Contract Lessee, operating lease, liability, term of contract Lessee, Operating Lease, Liability, Remaining Term Of Contract Lessee, Operating Lease, Liability, Remaining Term Of Contract Lessor, operating lease, weighted-average remaining lease term Lessor, Operating Lease, Weighted Average Remaining Lease Term Lessor, Operating Lease, Weighted Average Remaining Lease Term Statement of Cash Flows [Abstract] Cash Flows From Operating Activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Adjustments to Reconcile Net Income (Loss) to Net Cash Provided by Operating Activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Straight-line rental income Straight Line Rent Noncash operating lease expense Noncash Operating Lease, Expense Noncash Operating Lease, Expense Amortization Amortization of Intangible Assets Noncash interest expense Noncash interest expense The component of interest expense representing interest paid other than in cash for example by increasing the balance of debt securities and the noncash expenses charged against earnings in the period to amortize debt discount and premium associated with the related debt instruments. Income from unconsolidated joint ventures Distributions of earnings from unconsolidated joint ventures Proceeds from Equity Method Investment, Distribution Gain on sale of real estate assets Gain (Loss) on Sale of Properties Changes in assets and liabilities, net of acquisitions and dispositions: Changes in assets and liabilities, net of acquisitions [Abstract] Changes in assets and liabilities, net of acquisitions [Abstract] Decrease (increase) in tenant receivables, net Increase (Decrease) in Accounts Receivable Decrease (increase) in prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Decrease in accounts payable and accrued expenses Increase (Decrease) in Accounts Payable and Accrued Liabilities Increase (decrease) in deferred income Increase (Decrease) in Contract with Customer, Liability Net cash provided by operating activities Cash Flows From Investing Activities: Prepaid transaction costs and earnest money Payments for Deposits on Real Estate Acquisitions Capital improvement and development costs Payments to Acquire and Develop Real Estate Deferred lease costs paid Increase (Decrease) in Lease Acquisition Costs Cash Flows From Financing Activities: Financing costs paid Payments of Financing Costs Proceeds from lines of credit and notes payable Proceeds from Notes Payable Repayments of lines of credit and notes payable Repayments of Notes Payable Distributions paid to stockholders Payments of Dividends Redemptions of common stock Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Summary of Financial Information for the Joint Ventures Equity Method Investments [Table Text Block]