Derivative Contracts - Summary of Derivatives (Details) - Interest Rate Swap - Derivatives Designated as Cash Flow Hedges - Cash Flow Hedging $ in Thousands	Mar. 31, 2020 USD ($) instrument
Derivative [Line Items]
Number of Interest Rate Swaps \| instrument	47
Notional	$ 5,517,400
Percent of notional amount related to the Fund	100.00%
Unconsolidated Funds
Derivative [Line Items]
Number of Interest Rate Swaps \| instrument	1
Notional	$ 110,000
Percent of notional amount related to the Fund	100.00%
Forward swap
Derivative [Line Items]
Notional	$ 895,000
Future notional	$ 1,480,000

Derivative Notional Value, Future

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- Definition

Equity Method Investment, Summarized Financial Information, Percentage Of Notional Amount Of Derivative

+ References

No definition available.

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- Definition

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+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
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-Topic 815
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