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Related Costs, Share-based Payments [Text Block] Mortgage Notes Payable Mortgage Notes Payable Disclosure [Text Block] Equity Method Investments and Joint Ventures [Abstract] Condensed Balance Sheet Condensed Balance Sheet [Table Text Block] Condensed Income Statement Condensed Income Statement [Table Text Block] Statement of Financial Position [Abstract] Statement [Table] Statement [Table] Class of Stock [Axis] Class of Stock [Domain] Preferred Shares Preferred Stock [Member] Convertible Preferred Stock Convertible Preferred Stock [Member] Statement [Line Items] Statement [Line Items] ASSETS Assets [Abstract] Real estate investments, at cost: Real Estate Investment Property, at Cost [Abstract] Land Land Buildings, fixtures and improvements Buildings, Fixtures and Improvements Buildings, Fixtures and Improvements Acquired intangible assets Finite-Lived Intangible Asset, Acquired-in-Place Leases Total real estate investments, at cost Real Estate Investment Property, at Cost Less accumulated depreciation and amortization Real Estate Investment Property, Accumulated Depreciation Total real estate investments, net Real Estate Investment Property, Net Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Restricted cash Restricted Cash and Cash Equivalents Investment securities, at fair value Available-for-sale Securities Investments in unconsolidated joint venture Equity Method Investments Preferred equity investment Held-to-maturity Securities Derivatives, at fair value Derivative Asset Tenant and other receivables Accounts and Notes Receivable, Net Unbilled rent receivables Deferred Rent Receivables, Net Prepaid expenses and other assets Prepaid Expense and Other Assets Deferred costs, net Deferred Costs Total assets Assets LIABILITIES AND EQUITY Liabilities and Equity [Abstract] Mortgage notes payable Secured Debt Market lease intangibles, net Off-market Lease, Unfavorable Derivatives, at fair value Derivative Liability, Fair Value, Gross Liability Accounts payable, accrued expenses and other liabilities (including amounts due to affiliates of $278 and $575 as of March 31, 2015 and December 31, 2014, respectively) Accounts Payable and Accrued Liabilities Deferred rent Deferred Revenue, Leases, Gross Dividends payable Dividends Payable Total liabilities Liabilities Preferred stock Preferred Stock, Value, Issued Common stock, $0.01 par value; 300,000,000 shares authorized, 162,463,456 and 162,181,939 shares issued and outstanding at March 31, 2015 and December 31, 2014, respectively Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated deficit Retained Earnings (Accumulated Deficit) Total stockholders' equity Stockholders' Equity Attributable to Parent Non-controlling interests Stockholders' Equity Attributable to Noncontrolling Interest Total equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total liabilities and equity Liabilities and Equity Related Party Transactions [Abstract] Schedule of Related Party Transactions, by Related Party [Table] Schedule of Related Party Transactions, by Related Party [Table] Greater Of Greater Of [Member] Greater Of [Member] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] New York Recovery Advisors, LLC New York Recovery Advisors, LLC [Member] New York Recovery Advisors, LLC [Member] New York Recovery Advisors, LLC and Realty Capital Securities, LLC New York Recovery Advisors, LLC and Realty Capital Securities, LLC [Member] New York Recovery Advisors, LLC and Realty Capital Securities, LLC [Member] Related Party Fees, by Benchmark [Axis] Related Party Fees, by Benchmark [Axis] Related Party Fees, by Benchmark [Axis] Related Party Fees, Benchmark [Domain] Related Party Fees, Benchmark [Domain] Related Party Fees, Benchmark [Domain] Contract Purchase Price Contract Purchase Price [Member] Contract Purchase Price [Member] Average Invested Assets Average Invested Assets [Member] Average Invested Assets [Member] Gross Revenue, Multi-tenant Properties Gross Revenue, Multi-tenant Properties [Member] Gross Revenue, Multi-tenant Properties [Member] Gross Revenue, Managed Properties Gross Revenue, Managed Properties [Member] Gross Revenue, Managed Properties [Member] Amount Available or Outstanding Under Financing Arrangement Amount Available or Outstanding Under Financing Arrangement [Member] Amount Available or Outstanding Under Financing Arrangement [Member] Net Income, Excluding Additions to Non-cash Reserves and Gains on Sales of Assets Net Income, Excluding Additions to Non-cash Reserves and Gains on Sales of Assets [Member] Net Income, Excluding Additions to Non-cash Reserves and Gains on Sales of Assets [Member] Advisor Advisor [Member] Advisor [Member] Related Party Transaction [Line Items] Related Party Transaction [Line Items] Acquisition fees earned by related party Related Party Transaction, Acquisition Fees Earned by Related Party, Percentage of Benchmark Related Party Transaction, Acquisition Fees Earned by Related Party, Percentage of Benchmark Acquisition fees and acquisition related expenses earned by related party Related Party Transaction, Acquisition Fees and Acquisition Related Expenses Earned by Related Party, Percentage of Benchmark Expected total of acquisition fees and acquisition related expenses, percentage of benchmark Asset management fees as a percentage of benchmark Related Party Transaction, Asset Management Fees Earned by Related Party, Percentage of Benchmark Related Party Transaction, Asset Management Fees Earned by Related Party, Percentage of Benchmark Unearned units, in lieu of asset management fees (in shares) Unearned Class B Units, in Lieu of Asset Management Fees Paid in Cash Unearned Class B Units, in Lieu of Asset Management Fees Paid in Cash Equity-based compensation Allocated Share-based Compensation Expense Cost of assets maximum Advisory Agreement, Cost of Assets Maximum Advisory Agreement, Cost of Assets Maximum Asset management fees earned above Related Party Transaction, Asset Management Fees Earned Above Threshold Related Party Transaction, Asset Management Fees Earned Above Threshold Property management fees as a percentage of benchmark Related Party Transaction, Property Management Fees Earned by Related Party, Percentage of Benchmark Related Party Transaction, Property Management Fees Earned by Related Party, Percentage of Benchmark Oversight fees as a percentage of benchmark Related Party Transaction, Oversight Fees Earned by Related Party, Percentage of Benchmark Related Party Transaction, Oversight Fees Earned by Related Party, Percentage of Benchmark Financing coordination as a percentage of benchmark Related Party Transaction, Financing Coordination Fees Earned by Related Party, Percentage of Benchmark Related Party Transaction, Financing Coordination Fees Earned by Related Party, Percentage of Benchmark Operating expenses as a percentage of benchmark Related Party Transaction, Operating Expenses as a Percentage of Benchmark Related party transaction, operating expenses as a percentage of benchmark, fee cap Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Hedging Relationship [Axis] Hedging Relationship [Axis] Hedging Relationship [Domain] Hedging Relationship [Domain] Cash Flow Hedging Cash Flow Hedging [Member] Derivative, by Nature [Axis] Derivative, by Nature [Axis] Derivative, Name [Domain] Derivative, Name [Domain] Interest rate swaps Swap [Member] Hedging Designation [Axis] Hedging Designation [Axis] Hedging Designation [Domain] Hedging Designation [Domain] Designated as Hedging Instrument Designated as Hedging Instrument [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Derivatives at Fair Value Derivative Financial Instruments, Liabilities [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Derivative assets, at fair value Interest Rate Derivative Assets, at Fair Value Derivative liabilities, at fair value Interest Rate Derivative Liabilities, at Fair Value Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] Investment, Name [Axis] Investment, Name [Axis] Investment, Name [Domain] Investment, Name [Domain] Worldwide Plaza Worldwide Plaza [Member] Worldwide Plaza [Member] Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Ownership percentage Equity Method Investment, Ownership Percentage Aggregate cost Equity Method Investment, Aggregate Cost Agreed upon value Agreed Upon Value Agreed Upon Value Notes payable Notes Payable Interest rate Debt, Weighted Average Interest Rate Purchase obligation Unrecorded Unconditional Purchase Option Balance Sheet Amount Amount of the unrecorded option to transfer funds in the future for fixed or minimum amounts or quantities of good or services at fixed or minimum prices (for example, as in take-or-pay contracts through throughput contracts Fee for non-exercise of purchase option Fee for Non-Exercise of Purchase Option Fee for Non-Exercise of Purchase Option Purchase option term Purchase option term Purchase option term Difference between carrying amount and underlying equity Equity Method Investment, Difference Between Carrying Amount and Underlying Equity Income (loss) from unconsolidated joint venture Income (Loss) from Equity Method Investments, Net of Dividends or Distributions Proceeds from investment Proceeds from Equity Method Investment, Dividends or Distributions Amortization of difference in basis Amortization of Difference Between Carrying Amount and Equity Amortization of Difference Between Carrying Amount and Equity Company's share of net loss from Worldwide Plaza Income (Loss) from Equity Method Investments Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity [Table Text Block] Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Performance-Based Units, Performance Schedule Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Performance-Based Units, Performance Schedule [Table Text Block] Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Performance-Based Units, Performance Schedule [Table Text Block] Schedule of Fair Value, Liabilities Measured on Recurring Basis Fair Value, Liabilities Measured on Recurring Basis [Table Text Block] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation Fair Value, Liabilities Measured on Recurring Basis, Unobservable 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Fair Value, Inputs, Level 3 [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] OPP Share Based Compensation, Fair Value Liability Share Based Compensation, Fair Value Liability Rental income Operating Leases, Income Statement, Lease Revenue Other revenue Tenant Reimbursements Total revenues Revenues Property operating Direct Costs of Leased and Rented Property or Equipment Depreciation and amortization Depreciation, Depletion and Amortization, Nonproduction Total operating expenses Operating Expenses Operating income Operating Income (Loss) Interest expense Interest Expense Net loss Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Company's preferred distribution Preferred Stock Dividends and Other Adjustments Joint venture partner distributions General Partner Distributions Net loss attributable to stockholders Net Income (Loss) Attributable to Parent Company's preferred distribution Amortization of difference in basis Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Number of properties owned Number of Real Estate Properties Viceroy Hotel Viceroy Hotel [Member] Viceroy Hotel [Member] Special Limited Partner Special Limited Partner [Member] Special Limited Partner [Member] Sponsor Sponsor [Member] Sponsor [Member] Affiliated Entity Affiliated Entity [Member] Related Party Transaction [Axis] Related Party Transaction [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] Real Estate Investment Fund Real Estate Investment Fund [Member] Real Estate Investment Fund [Member] Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Related party transaction, amount Related Party Transaction, Amounts of Transaction Due from affiliates Due from Affiliates Revenue from Related Parties Revenue from Related Parties Commitments and Contingencies Disclosure [Abstract] Schedule of Future Minimum Rental Payments for Operating Leases Schedule of Future Minimum Rental Payments for Master Leases [Table Text Block] Schedule of Future Minimum Rental Payments for Master Leases [Table Text Block] Schedule of Capital Leased Assets Schedule of Capital Leased Assets [Table Text Block] Income Statement [Abstract] Revenues: Revenues [Abstract] Hotel revenue Revenue from Hotels Operating expense reimbursements and other revenue Operating expenses: Operating Expenses [Abstract] Hotel operating Direct Costs of Hotels Operating fees to affiliates Asset Management Costs Acquisition and transaction related Business Combination, Acquisition Related Costs General and administrative General and Administrative Expense Operating loss Other income (expenses): Nonoperating Income (Expense) [Abstract] Interest expense Income from preferred equity investment, investment securities and interest Investment Income, Net Loss on derivative instruments Gain (Loss) on Derivative Instruments, Net, Pretax Total other expenses Nonoperating Income (Expense) Net loss (income) attributable to non-controlling interests Net Income (Loss) Attributable to Noncontrolling Interest Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Change in unrealized loss on derivatives Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Unrealized gain on investment securities Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax Total other comprehensive loss Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Comprehensive loss attributable to stockholders Comprehensive Income (Loss), Net of Tax, Attributable to Parent Basic and diluted net loss per share attributable to stockholders (in dollars per share) Earnings Per Share, Basic and Diluted Earnings Per Share [Abstract] 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] Unvested restricted stock Restricted Stock [Member] OP units OP Units [Member] OP Units [Member] Class B units Class B Units [Member] Class B Units [Member] LTIP units LTIP Units [Member] LTIP Units [Member] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Total anti-dilutive common share equivalents (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Schedule of Amount Contractually Due and Forgiven in Connection With Operation Related Services Schedule of Amount Contractually Due and Forgiven in Connection With Operation Related Services [Table Text Block] Schedule of Amount Contractually Due and Forgiven in Connection With Operation Related Services [Table Text Block] Net Loss Per Share Earnings Per Share [Text Block] Equity [Abstract] Accumulated Other Comprehensive Income (Loss) Stockholders' Equity Note Disclosure [Text Block] Investments, Debt and Equity Securities [Abstract] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Redeemable Preferred Stock Redeemable Preferred Stock [Member] Equity securities Equity Securities [Member] Investment Securities Class [Axis] Investment Securities Class [Axis] Investment Securities Class [Domain] Investment Securities Class [Domain] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Cost Available-for-sale Equity Securities, Amortized Cost Basis Gross Unrealized Gains Available-for-sale Equity Securities, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Losses Available-for-sale Equity Securities, Accumulated Gross Unrealized Loss, before Tax Fair Value PeriodFromIssuanceWhenInvestmentsBecomeRedeemable PeriodFromIssuanceWhenInvestmentsBecomeRedeemable Period From Issuance When Investments Become Redeemable Transaction Fee Upon Consummation of the Sale Transaction Fee Upon Consummation of the Sale [Member] Transaction Fee Upon Consummation of the Sale [Member] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Tender Offer Tender Offer [Member] Tender Offer [Member] Contract Sales Price Contract Sales Price [Member] Contract Sales Price [Member] Related Party Transactions, by Cost [Axis] Related Party Transactions, by Cost [Axis] Related Party Transactions, by Cost [Axis] Related Party Transactions, Cost [Domain] Related Party Transactions, Cost [Domain] Related Party Transactions, Cost [Domain] Transaction Management Transaction Management [Member] Transaction Management Information Agent and Advisory Service Fee Information Agent and Advisory Service Fee [Member] Information Agent and Advisory Service Fee [Member] Fees and expense reimbursements from the Advisor and Dealer Manager Fees and Expense Reimbursement, Stock Offering [Member] Fees And Expense Reimbursement, Stock Offering [Member] Brokerage Commission Fees Brokerage Commission Fees [Member] Brokerage Commission Fees [Member] Real Estate Commissioner Real Estate Commissions [Member] Real Estate Commissions [Member] Realty Capital Securities, LLC and American National Stock Transfer, LLC Realty Capital Securities, LLC and American National Stock Transfer, LLC [Member] Realty Capital Securities, LLC and American National Stock Transfer, LLC [Member] RCS Advisory Services, LLC RCS Advisory Services, LLC [Member] RCS Advisory Services, LLC [Member] Dealer Manager and Transfer Agent Dealer Manager and Transfer Agent [Member] Dealer Manager and Transfer Agent [Member] Dealer Manager Dealer Manager [Member] Dealer Manager [Member] Transaction management fee Related Party Fee, Transaction Management Fee Earned By Related Party, Total Liability Related Party Fee, Transaction Management Fee Earned By Related Party, Total Liability Fees paid to related parties Related Party Transaction, Expenses from Transactions with Related Party Shares authorized (in shares) Stock Repurchase Program, Number of Shares Authorized to be Repurchased Information agent and advisory service fee Related Party Fee, Information Agent and Advisory Service Fee Earned by Related Party Related Party Fee, Information Agent and Advisory Service Fee Earned by Related Party Transaction fee earned Related Party Transaction, Transaction Fee Earned By Related Party, Percentage of Benchmark Related Party Transaction, Transaction Fee Earned By Related Party, Percentage of Benchmark Real estate commission earned by related party Related Party Transaction, Real Estate Commission Earned by Related Party, Percentage of Benchmark Related Party Transaction, Real Estate Commission Earned by Related Party, Percentage of Benchmark Investment in Unconsolidated Joint Venture Equity Method Investments and Joint Ventures Disclosure [Text Block] Schedule of Mortgage Notes Payable Schedule of Long-term Debt Instruments [Table Text Block] Schedule Of Aggregate Principal Payments On Mortgages Schedule of Maturities of Long-term Debt [Table Text Block] Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Table] Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Table] Valuation Technique [Axis] Valuation Technique [Axis] Valuation Technique [Domain] Valuation Technique [Domain] Monte Carlo Simulation Monte Carlo Simulation [Member] Monte Carlo Simulation [Member] Liability Class [Axis] Liability Class [Axis] Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Share Based Compensation Liability Share Based Compensation Liability [Member] Share Based Compensation Liability [Member] Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items] Expected volatility Fair Value Assumptions, Expected Volatility Rate Statement of Cash Flows [Abstract] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Net loss Adjustments to reconcile net loss to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation and amortization Depreciation Amortization of deferred financing costs Amortization of Financing Costs Accretion of below- and amortization of above-market lease liabilities and assets, net Accretion of Below-Market Lease Liabilities and Amortization of Above-Market Lease Assets, Net Adjustment for noncash decrease (increase) in rental revenue related to assets (liabilities) associated with the acquisition of an off-market lease when the terms of the lease are favorable (unfavorable) to the market terms for the lease at the date of acquisition. Share-based compensation Share-based Compensation Loss (income) from unconsolidated joint venture Gain on sale of investment securities Marketable Securities, Gain (Loss), Excluding Other than Temporary Impairments Bad debt expense Provision for Doubtful Accounts Changes in assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Tenant and other receivables Increase (Decrease) in Accounts and Other Receivables Unbilled rent receivables Increase (Decrease) in Unbilled Receivables Prepaid expenses, other assets and deferred costs Increase (Decrease) in Prepaid Expense and Other Assets Accrued unbilled ground rent Increase (Decrease) in Unbilled Rent Receivables Increase (Decrease) in Unbilled Rent Receivables Accounts payable and accrued expenses Increase (Decrease) in Accounts Payable and Accrued Liabilities Deferred rent and other liabilities Increase (Decrease) in Deferred Revenue 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] Proceeds from sale of preferred equity investment Proceeds from Preferred Equity Investment Proceeds from Preferred Equity Investment Acquisition funds released from escrow Increase in Restricted Cash Additional investment in unconsolidated joint venture Payments to Acquire Interest in Joint Venture Capital expenditures Payments for Capital Improvements Distributions from unconsolidated joint venture Proceeds From Equity Method Investment Dividends Or Distributions Proceeds From Equity Method Investment Dividends Or Distributions Proceeds from sale of investment securities Proceeds from Sale and Maturity of Marketable Securities Purchase of investment securities Payments to Acquire Available-for-sale Securities Net cash provided by investing activities Net Cash Provided by (Used in) Investing Activities Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Payments on mortgage notes payable Repayments of Secured Debt Payments of financing costs Payments of Financing Costs Proceeds from issuance of common stock Proceeds from Issuance of Common Stock Repurchases of common stock, inclusive of fees and expenses Payments for Repurchase of Common Stock Payments of offering costs and fees related to stock issuances Payments of Stock Issuance Costs Dividends paid Payments of Dividends Distributions to non-controlling interest holders Distributions To Non-controlling Interest Holders Distributions to noncontrolling interest holders. Restricted cash Proceeds from (Repayments of) Restricted Cash, Financing Activities Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Net increase in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of period Cash and cash equivalents, end of period Supplemental disclosures: Supplemental Cash Flow Information [Abstract] Cash paid for interest Interest Paid Accrued capital expenditures Capital Expenditures Incurred but Not yet Paid Common stock issued through distribution reinvestment plan Conversion of Stock, Amount Issued Fair Value Disclosures [Abstract] Financial Instrument [Axis] Financial Instrument [Axis] Types of Financial Instruments [Domain] Financial Instruments [Domain] Interest rate swaps, net Interest Rate Swap [Member] Investment securities Available-for-sale Securities [Member] Interest rate swaps, net Derivative Assets (Liabilities), at Fair Value, Net Investment securities April 1, 2015 - December 31, 2015 Operating Leases, Future Minimum Payments Receivable, Remainder of Fiscal Year 2016 Operating Leases, Future Minimum Payments Receivable, in Two Years 2017 Operating Leases, Future Minimum Payments Receivable, in Three Years 2018 Operating Leases, Future Minimum Payments Receivable, in Four Years 2019 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 Capital Leased Assets [Table] Schedule of Capital Leased Assets [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] Building and Building Improvements Building and Building Improvements [Member] Capital Leased Assets [Line Items] Capital Leased Assets [Line Items] Buildings, fixtures and improvements Capital Leased Assets, Gross Less accumulated depreciation and amortization Capital Leases, Lessee Balance Sheet, Assets by Major Class, Accumulated Depreciation Total real estate investments, net Capital Leases, Balance Sheet, Assets by Major Class, Net Class of Stock [Axis] Class of Stock [Domain] Due to affiliate Due to Related Parties Common stock, par value (in dollars 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 Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Gross Amounts of Recognized Assets Derivative Asset, Fair Value, Gross Asset Gross Amounts of Recognized Liabilities Net Amounts of Assets (Liabilities) presented on the Balance Sheet Derivative Liability Financial Instruments Derivative, Collateral, Obligation to Return Securities Cash Collateral Posted Derivative, Collateral, Obligation to Return Cash Net Amount Derivative Liability, Fair Value, Amount Offset Against Collateral Fair Value, by Balance Sheet Grouping Fair Value, by Balance Sheet Grouping [Table Text Block] Derivative [Table] Derivative [Table] Derivative Instrument Risk [Axis] Derivative Instrument [Axis] Derivative Contract Type [Domain] Derivative Contract [Domain] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Interest Expense Interest Expense [Member] Derivative [Line Items] Derivative [Line Items] Interests reclassified to AOCI Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimate of Time to Transfer Interests reclassified to AOCI period Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred Fair value of derivatives Derivative Liability, Current Amount required to settle its obligations under the agreement at its aggregate termination value incase of breach Assets Needed for Immediate Settlement, Aggregate Fair Value Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Mortgages Mortgages [Member] Name of Property [Axis] Name of Property [Axis] Name of Property [Domain] Name of Property [Domain] Design Center Interior Design Building [Member] Interior Design Building [Member] Bleecker Street Bleecker Street [Member] Bleecker Street [Member] Foot Locker Foot Locker [Member] Foot Locker [Member] Regal Parking Garage Regal Parking Garage [Member] Regal Parking Garage [Member] Duane Reade Duane Reed [Member] Duane Reed [Member] Washington Street Portfolio Washington Street [Member] Washington Street [Member] One Jackson Square One Jackson Square [Member] One Jackson Square [Member] 350 West 42nd Street 42nd Street [Member] 42nd Street [Member] 1100 Kings Highway Kings Highway Portfolio [Member] Kings Highway Portfolio [Member] 1623 Kings Highway 1623 Kings Highway Portfolio [Member] 1623 Kings Highway Portfolio [Member] 256 West 38th Street 256 West 38th Street [Member] 256 West 38th Street [Member] 229 West 36th Street 229 West 36th Street [Member] 229 West 36th Street [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Encumbered Properties Number of Real Estate Properties, Encumbered Number of Real Estate Properties, Encumbered Outstanding Loan Amount Effective Interest Rate Real estate investments at cost related to mortgages Real Estate Investment, At Cost Relating to Notes Payable Real Estate Investment, At Cost Relating to Notes Payable Accounting Policies [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Stockholders' Equity Note [Abstract] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Common stock Common Stock [Member] Class of Stock [Line Items] Class of Stock [Line Items] Payments for Repurchase of Common Stock Dividends declared (in dollars per share) Common Stock, Dividends, Per Share, Declared Dividends declared per day (in dollars per share) Common Stock, Dividends, Per Share Per Day, Declared Common Stock, Dividends, Per Share Per Day, Declared Related Party Transactions, by Cost Status [Axis] Related Party Transactions, by Cost Status [Axis] Related Party Transactions, by Cost Status [Axis] Related Party Transactions, Cost Status [Domain] Related Party Transactions, Cost Status [Domain] Related Party Transactions, Cost Status [Domain] Incurred Incurred [Member] Incurred [Member] Forgiven Forgiven [Member] Forgiven [Member] Asset Management Fees Asset Management Fees [Member] Asset Management Fees [Member] Transfer agent and other professional fees Transfer Agent and Other Professional Fees [Member] Transfer Agent and other professional fees [Member] Property management and leasing fees Property Management and Leasing Fees [Member] Property Management and Leasing Fees [Member] Dividends on Class B units Distributions On Class B Units [Member] Distributions On Class B Units [Member] Related Party Transaction, by Frequency [Axis] Related Party Transaction, by Frequency [Axis] Related Party Transaction, by Frequency [Axis] Related Party Transaction, Frequency [Domain] Related Party Transaction, Frequency [Domain] Related Party Transaction, Frequency [Domain] Ongoing fees: Recurring Fees [Member] Recurring Fees [Member] Due to affiliates, net Due to Affiliate Derivative Instruments, Gain (Loss) by Hedging Relationship, by Income 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Events [Text Block] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Award Type [Axis] Award Type [Domain] Equity Award [Domain] Stock Options Employee Stock Option [Member] Restricted Stock Stock Option Plan Stock Option Plan [Member] Stock Option Plan [Member] Restricted Share Plan Restricted Share Plan [Member] Restricted Share Plan [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Exercise price for all stock options granted under the Plan (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercise Price Number of shares authorized (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Shares automatically granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Automatic Grant Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Automatic Grant Vesting percentage Share-based Compensation Arrangement by Share-based Payment Award, Periodic Vesting Percentage Share-based Compensation Arrangement by Share-based Payment Award, Periodic Vesting Percentage Maximum authorized amount as a percentage of shares authorized Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum Maximum percent of awards as a percent of total outstanding Maximum Percent of Awards as a Percent of Total Outstanding Maximum Percent of Awards as a Percent of Total Outstanding Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Share-based payment award, award vesting rights Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Compensation cost not yet recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Shares expected to vest Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Unrealized gains on available-for-sale securities Accumulated Net Unrealized Investment Gain (Loss) [Member] Designated derivatives fair value adjustment Accumulated Net Gain (Loss) from Designated or Qualifying Cash Flow Hedges [Member] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward] Accumulated Other Comprehensive Income (Loss), Net of Tax Other comprehensive income (loss), before reclassifications Other Comprehensive Income (Loss), before Reclassifications, Net of Tax Amounts reclassified from accumulated other comprehensive income (loss) Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax Net current-period other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Income (Loss), Net of Tax Reclassifications Reclassification, Policy [Policy Text Block] Common Stock Real estate assets, at cost Less accumulated depreciation and amortization Other assets Other Assets Debt Other liabilities Other Liabilities Deficit Company's basis Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Beginning Balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number Ending Balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Beginning Balance (in 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 (in 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 Ending Balance (in dollars per share) Preferred Equity Investment Preferred Equity Investments [Text Block] Preferred Equity Investments Statement of Stockholders' Equity [Abstract] Common Stock Additional Paid-In Capital Additional Paid-in Capital [Member] Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Income (Loss) [Member] Accumulated Deficit Retained Earnings [Member] Total Stockholders' Equity Parent [Member] Non- controlling Interests Noncontrolling Interest [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Beginning Balance (in shares) Shares, Outstanding Beginning Balance Equity-based compensation (in shares) Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Equity-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Distributions to non-controlling interest holders Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Dividends declared Dividends Net loss Other comprehensive loss Ending Balance (in shares) Ending Balance Number of Instruments Number of Interest Rate Derivatives Held Notional Amount Derivative, Notional Amount Schedule of Future Minimum Rental Payments for Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Schedule of Annualized Rental Income by Major Tenants Schedule of Annualized Rental Income by Major Tenants [Table Text Block] Schedule of Annualized Rental Income By Tenants Greater Than 10% of Total Annualized Rental Income [Table Text Block] Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] April 1, 2015 - December 31, 2015, Operating Leases Operating Leases, Future Minimum Payments, Remainder of Fiscal Year 2016, Operating Leases Operating Leases, Future Minimum Payments, Due in Two Years 2017, Operating Leases Operating Leases, Future Minimum Payments, Due in Three Years 2018, Operating Leases Operating Leases, Future Minimum Payments, Due in Four Years 2019, Operating Leases Operating Leases, Future Minimum Payments, Due in Five Years Thereafter, Operating Leases Operating Leases, Future Minimum Payments, Due Thereafter Total, Operating Leases Operating Leases, Future Minimum Payments Due Capital Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Capital Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] April 1, 2015 - December 31, 2015, Operating Leases Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year 2016, Operating Leases Capital Leases, Future Minimum Payments Due in Two Years 2017, Operating Leases Capital Leases, Future Minimum Payments Due in Three Years 2018, Operating Leases Capital Leases, Future Minimum Payments Due in Four Years 2019, Operating Leases Capital Leases, Future Minimum Payments Due in Five Years Thereafter, Operating Leases Capital Leases, Future Minimum Payments Due Thereafter Total, Operating Leases Capital Leases, Future Minimum Payments Due Less: amounts representing interest Capital Leases, Future Minimum Payments, Interest Included in Payments Total present value of minimum lease payments Capital Leases, Future Minimum Payments, Present Value of Net Minimum Payments Interest Rate Derivatives and Hedging Activities Derivative Instruments and Hedging Activities Disclosure [Text Block] Investment Securities Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Economic Dependency [Abstract] Economic Dependency [Abstract] Economic Dependency Economic Dependency [Text Block] Matters related to services provided by affiliate. Noncontrolling Interest [Abstract] Non-Controlling Interests Noncontrolling Interest Disclosure [Text Block] Fair Value Of Financial Instruments Fair Value Disclosures [Text Block] Current pay rate Preferred Equity Investment, Current Pay Rate Preferred Equity Investment, Current Pay Rate Current accrual rate Preferred Equity Investment, Current Accrual Rate Preferred Equity Investment, Current Accrual Rate Interest Income from preferred equity investment Interest Income from Preferred Equity Investment Interest Income from Preferred Equity Investment Interest Expense Capital Leases, Income Statement, Interest Expense Rent Expense Operating Leases, Rent Expense Net loss attributable to stockholders (In thousands) Basic weighted average shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic and Diluted Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Beginning Balance Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value Fair value adjustment Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Period Increase (Decrease) Ending Balance Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Funding Component, by Type [Axis] Funding Component, by Type [Axis] Funding Component, by Type [Axis] Funding Component, By Type [Domain] Funding Component, By Type [Domain] Funding Component, By Type [Domain] Relative Component Relative Component [Member] Relative Component [Member] Absolute Component Absolute Component [Member] Absolute Component [Member] Funding Component, by Benchmark [Axis] Funding Component, by Benchmark [Axis] Funding Component, by Benchmark [Axis] Funding Component, By Benchmark [Domain] Funding Component, By Benchmark [Domain] Funding Component, By Benchmark [Domain] Excess Return, Above Threshold Excess Return, Above Threshold [Member] Excess Return, Above Threshold [Member] Excess Return, Above Peer Group Excess Return, Above Peer Group [Member] Excess Return, Above Peer Group [Member] Cumulative Return, Above Threshold Cumulative Return, Above Threshold [Member] Cumulative Return, Above Threshold [Member] Cumulative Return, Equal to Threshold Cumulative Return, Equal to Threshold [Member] Cumulative Return, Equal to Threshold [Member] Cumulative Return, Below Threshold Cumulative Return, Below Threshold [Member] Cumulative Return, Below Threshold [Member] New Multi-Year Outperformance Plan New Multi-Year Outperformance Plan [Member] New Multi-Year Outperformance Plan [Member] Performance Shares Performance Shares [Member] Vesting [Axis] Vesting [Axis] Vesting [Domain] Vesting [Domain] Performance Period Performance Period [Member] Performance Period [Member] Annual Period Annual Period [Member] Annual Period [Member] Interim Period Interim Period [Member] Interim Period [Member] Opp units issued (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Award Opportunity Amount Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Award Opportunity Amount Company's market capitalization percentage Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Award Opportunity, Percentage of Equity Market Capitalization Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Maximum Award Opportunity, Percentage of Equity Market Capitalization Absolute Component: 4% of any excess Total Return attained above an absolute hurdle measured from the beginning of such period: Share-based Compensation Arrangement by Share-based Payment Award, Absolute Component, Performance Target Percentage Share-based Compensation Arrangement by Share-based Payment Award, Absolute Component, Performance Target Percentage 100% will be earned if cumulative Total Return achieved is at least: Share-based Compensation Arrangement by Share-based Payment Award, Relative Component, One Hundred Percent Funding Benchmark, Performance Target Percentage Share-based Compensation Arrangement by Share-based Payment Award, Relative Component, One Hundred Percent Funding Benchmark, Performance Target Percentage 50% will be earned if cumulative Total Return achieved is: Share-based Compensation Arrangement by Share-based Payment Award, Relative Component, Fifty Percent Funding Benchmark, Performance Target Percentage Share-based Compensation Arrangement by Share-based Payment Award, Relative Component, Fifty Percent Funding Benchmark, Performance Target Percentage 0% will be earned if cumulative Total Return achieved is less than: Share-based Compensation Arrangement by Share-based Payment Award, Relative Component, Zero Percent Funding Benchmark, Performance Target Percentage Share-based Compensation Arrangement by Share-based Payment Award, Relative Component, Zero Percent Funding Benchmark, Performance Target Percentage Return percentage threshold Share-based Compensation Arrangement by Share-based Payment Award, Return Percentage Threshold Share-based Compensation Arrangement by Share-based Payment Award, Return Percentage Threshold Shares authorized, percentage of benchmark Share-based Compensation Arrangement by Share-based Payment Award, Shares Authorized, Percentage of Benchmark Share-based Compensation Arrangement by Share-based Payment Award, Shares Authorized, Percentage of Benchmark Shares awarded as a percentage of maximum Share-based Compensation Arrangement by Share-based Payment Award, Shares Awarded as a Percentage of Maximum Share-based Compensation Arrangement by Share-based Payment Award, Shares Awarded as a Percentage of Maximum Distribution entitlement percentage Distribution Entitlement Percentage Distribution Entitlement Percentage Payments of Dividends Noncontrolling Interest [Table] Noncontrolling Interest [Table] 163 Washington Ave Condominiums 163 Washington Ave Condominiums [Member] 163 Washington Ave Condominiums [Member] Noncontrolling Interest [Line Items] Noncontrolling Interest [Line Items] Nonvested Shares outstanding (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Distributions to non-controlling interest holders Noncontrolling members' aggregate investment Noncontrolling Interest, Initial Investment by Noncontrolling Owners Investment of non-controlling interest holders April 1, 2015 - December 31, 2015 Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months 2016 Long-term Debt, Maturities, Repayments of Principal in Year Two 2017 Long-term Debt, Maturities, Repayments of Principal in Year Three 2018 Long-term Debt, Maturities, Repayments of Principal in Year Four 2019 Long-term Debt, Maturities, Repayments of Principal in Year Five Thereafter Long-term Debt, Maturities, Repayments of Principal after Year Five Total Schedule of Available-for-sale Securities Reconciliation Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Schedule of Revenue by Major Customers, by Reporting Segments [Table] Schedule of Revenue by Major Customers, by Reporting Segments [Table] Major Customers [Axis] Customer [Axis] Name of Major Customer [Domain] Customer [Domain] Cravath, Swaine & Moore, LLP Cravath, Swaine & Moore, LLP [Member] Cravath, Swaine & Moore, LLP [Member] Nomura Holdings America, Inc. Nomura Holdings America, Inc. [Member] Nomura Holdings America, Inc. [Member] Revenue, Major Customer [Line Items] Revenue, Major Customer [Line Items] Major tenant rental income, as a percentage of total annualized rental income Concentration Risk, Percentage Credit Facility Revolving Credit Facility [Text Block] Revolving Credit Facility [Text Block] Related Party Transactions and Arrangements Related Party Transactions Disclosure [Text Block] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Level 3 Mortgage notes payable Preferred Equity Investment Preferred Equity Investment [Member] Preferred Equity Investment [Member] Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [Axis] Measurement Basis [Axis] Fair Value, Disclosure Item Amounts [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Carrying Amount Reported Value Measurement [Member] Fair Value Estimate of Fair Value Measurement [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Debt, fair value Debt Instrument, Fair Value Disclosure Document and Entity Information [Abstract] Document and Entity Information [Abstract] 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 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