Debt Obligations - Aggregate Scheduled Principal Payments of Debt Obligation, Excluding Amortization of Discounts and Premiums (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
2020 (six months remaining)	$ 83,317
2021	15,143
2022	317,332
2023	556,736
2024	350,000
Thereafter	878,610
Total principal payments	2,201,138
Net unamortized premiums/(discounts)	9,918
Net deferred financing costs	(9,301)
Outstanding indebtedness	2,201,755
Held for sale
Debt Instrument [Line Items]
2020 (six months remaining)	3,000
2021	6,100
2022	6,300
2023	206,700
Net unamortized premiums/(discounts)	(1,200)
Net deferred financing costs	(200)
Outstanding indebtedness	220,720
Held for use
Debt Instrument [Line Items]
Outstanding indebtedness	$ 1,981,035	$ 2,144,418

Long term-debt maturities repayments of principal

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Long-Term Debt, Maturity, After Year Four

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in remainder of current fiscal year.

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