Fair Value of Financial Instruments - Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Derivative Assets:
Fair value - consolidated derivatives	$ 0	$ 22,381
Derivative Liabilities:
Fair value - consolidated derivatives	$ 259,293	54,616
Fund X \| Interest Rate Swap
Derivative Liabilities:
Percent of notional amount related to the Fund	100.00%
Level 2
Derivative Assets:
Fair value - consolidated derivatives	$ 0	22,381
Derivative Liabilities:
Fair value - consolidated derivatives	259,293	54,616
Level 2 \| Fund X
Derivative Assets:
Fair value - unconsolidated Funds' derivatives	0	889
Derivative Liabilities:
Fair value - unconsolidated Funds' derivatives	$ 543	$ 0

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