Stockholders' Equity - Reclassification out of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other gain (loss), net	$ 9,680	$ (2,688)	$ (130,115)	$ (13,829)
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			(50,677)
Reclassification out of AOCI | Impairment of real estate securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other gain (loss), net			$ (31,844)