Condensed Consolidated Statement of Cash Flows - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Cash flows provided by (used in) operating activities:
Net cash provided by (used in) operating activities		$ 9,164	$ 28,867
Cash Flows from Investing Activities:
Purchase of securities		(761,382)	(827,252)
Purchase of loans		(302,567)	(273,571)
Capital improvements of real estate owned		(473)	0
Proceeds from disposition of securities		285,767	1,241,449
Proceeds from disposition of loans		0	38
Contributions to investments in unconsolidated entities		200	(3,034)
Distributions from investments in unconsolidated entities		12,971	13,824
Proceeds from disposition of real estate owned		336	6,946
Proceeds from principal payments of securities		108,082	135,093
Proceeds from principal payments of loans		53,586	154,441
Proceeds from investments sold short		86,373	201,998
Repurchase of securities sold short		(25,219)	(265,932)
Payments on financial derivatives		(14,566)	(48,081)
Proceeds from financial derivatives		18,138	26,877
Payments made on reverse repurchase agreements		(1,866,265)	(5,880,200)
Proceeds from reverse repurchase agreements		1,806,591	5,940,600
Due from brokers, net		6,044	(3,029)
Due to brokers, net		2,088	8,287
Net cash provided by (used in) investing activities		(590,296)	428,454
Cash flows provided by (used in) financing activities:
Net proceeds from issuance of common stock	[1]	0	95,537
Offering costs paid		0	(253)
Repurchase of common stock		0	(3,035)
Dividends paid		(15,273)	(21,024)
Contributions from non-controlling interests		1,159	3,487
Distributions to non-controlling interests		(5,923)	(4,798)
Proceeds from issuance of other secured borrowings		20,634	31,913
Principal payments on other secured borrowings		(7,990)	(10,662)
Borrowings under repurchase agreements		1,495,139	1,856,666
Repayments of repurchase agreements		(1,043,777)	(2,267,741)
Proceeds from Issuance of Other Secured Borrowings, at fair value		211,187	0
Due from brokers, net		(34,815)	(73,544)
Due to brokers, net		(1,506)	571
Net cash provided by (used in) financing activities		618,835	(392,883)
Net Increase (Decrease) in Cash, Cash Equivalents, and Restricted Cash		37,703	64,438
Cash, Cash Equivalents, and Restricted Cash, Beginning of Period		111,822	72,477
Cash, Cash Equivalents, and Restricted Cash, End of Period		149,525	136,915
Supplemental disclosure of cash flow information:
Interest paid		12,660	24,126
Income tax paid		(7)	0
Dividends payable		5,740	7,952
Transfers from mortgage loans to real estate owned (non-cash)		12,554	1,422
Transfers from mortgage loans to investments in non-consolidated entities (non-cash)		12,600	10,833
Purchase of Loans Non Cash		800	6,270
Principal payments on Other secured borrowings, at fair value (non-cash)		(92,930)	(44,704)
Proceeds received from Other secured borrowings, at fair value (non-cash)		39,321	0
Proceeds from issuance of Other secured borrowings (non-cash)		800	6,270
Proceeds from principal payments of investments (non-cash)		92,930	44,704
Repayments of repurchase agreement (non-cash)		$ (38,782)	$ 0

[1] Net of underwriters' discounts.