Real Estate Securities - Gains (Losses) on Real Estate Securities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Investments, Debt and Equity Securities [Abstract]
Unrealized gain/(loss) available-for-sale securities	$ (67,607)	$ 145
Reclassification of net (gain)/loss on available-for-sale securities included in net income (loss) from sales of securities	0	0
Unrealized gain/(loss) available-for-sale securities, net of reclassification adjustment	$ (67,607)	$ 145

Amount after tax and reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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