Debt - Mortgage Notes Payable - Summary of Mortgage Notes Payable Activity (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Mortgage notes payable, net beginning balance	$ 2,385,470	$ 3,618,722
Proceeds	295,771	96,935
Lump sum payoffs	(743,021)	(1,347,939)	$ (493,420)
Scheduled principal repayments	(6,808)	(6,629)
Amortization of premiums/ discounts	8,618	20,144	1,172
Amortization of deferred financing costs, net	1,580	4,237
Mortgage notes payable, net ending balance	1,941,610	2,385,470	3,618,722
Fixed Rate Debt [Member] \| Secured – Conventional [Member]
Debt Instrument [Line Items]
Mortgage notes payable, net beginning balance	1,885,407	2,982,344
Proceeds	288,120
Lump sum payoffs	(584,536)	(1,093,705)
Scheduled principal repayments	(6,308)	(6,029)
Amortization of premiums/ discounts	(7,999)	719
Amortization of deferred financing costs, net	15	2,078
Mortgage notes payable, net ending balance	1,574,699	1,885,407	2,982,344
Floating Rate Debt [Member]
Debt Instrument [Line Items]
Mortgage notes payable, net beginning balance	500,063	636,378
Proceeds	7,651	96,935
Lump sum payoffs	(158,485)	(254,234)
Scheduled principal repayments	(500)	(600)
Amortization of premiums/ discounts	16,617	19,425
Amortization of deferred financing costs, net	1,565	2,159
Mortgage notes payable, net ending balance	366,911	500,063	636,378
Floating Rate Debt [Member] \| Secured – Conventional [Member]
Debt Instrument [Line Items]
Mortgage notes payable, net beginning balance	6,357	6,948
Proceeds	7,651
Lump sum payoffs	(5,920)
Scheduled principal repayments	(500)	(600)
Amortization of deferred financing costs, net	(538)	9
Mortgage notes payable, net ending balance	7,050	6,357	6,948
Floating Rate Debt [Member] \| Secured – Tax Exempt [Member]
Debt Instrument [Line Items]
Mortgage notes payable, net beginning balance	493,706	629,430
Proceeds		96,935
Lump sum payoffs	(152,565)	(254,234)
Amortization of premiums/ discounts	16,617	19,425
Amortization of deferred financing costs, net	2,103	2,150
Mortgage notes payable, net ending balance	$ 359,861	$ 493,706	$ 629,430

Amount of amortization of other deferred financing costs net associated with mortgage notes payable, net.

No definition available.

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- Definition

The component of interest expense representing the noncash expenses charged against earnings in the period to amortize debt discount and premium associated with the mortgage notes payable during the period.

+ References

No definition available.

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- Definition

The cash outflow from the lump sum payment of collateralized debt obligations (backed by pledge, mortgage or other lien in the entity's assets).

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The cash inflow from borrowings supported by a written promise to pay an obligation that is collateralized (backed by pledge, mortgage or other lien in the entity's assets).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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