Stockholders' Equity - Reclassification out of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other gain (loss), net	$ (119,633)	$ (6,062)	$ (139,795)	$ (11,141)
Reclassification out of AOCI | Realized loss on sale of real estate securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other gain (loss), net	(57,364)
Reclassification out of AOCI | Impairment of real estate securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other gain (loss), net	$ (26,905)