CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash Flows From Operating Activities:
Net income/(loss)	$ 152,236	$ (812,417)
Adjustments to reconcile net income to net cash provided by operating activities:
(Gains)/losses on residential whole loans and real estate owned, net	(41,418)	346,372
Gains on securities, net	(1,476)	(71,430)
Impairment and other losses on securities available-for-sale and other assets	0	424,745
Loss on terminated swaps previously designed as hedges for accounting purposes	0	49,857
Accretion of purchase discounts on residential whole loans and securities	(34,322)	(20,244)
Amortization of purchase premiums on residential whole loans and securities, and amortization of terminated hedging instruments	15,669	35,594
(Reversal of provision)/provision for credit and valuation losses on residential whole loans and other financial instruments	(33,234)	65,334
Net other non-cash losses included in net income	9,214	42,540
Decrease in other assets	18,092	22,084
Increase/(decrease) in other liabilities	11,835	(25,791)
Net cash provided by operating activities	96,596	56,644
Cash Flows From Investing Activities:
Purchases of residential whole loans, loan related investments and capitalized advances	(1,032,791)	(1,285,106)
Proceeds from sales of residential whole loans, and residential whole loan repurchases	0	1,505,458
Principal payments on residential whole loans and loan related investments	917,553	862,480
Purchases of securities	0	(163,748)
Proceeds from sales of securities and other assets	0	3,790,032
Principal payments on securities	110,320	590,921
Purchases of real estate owned and capital improvements	(624)	(8,798)
Proceeds from sales of real estate owned	88,625	113,359
Additions to leasehold improvements, furniture and fixtures	(43,589)	837
Net cash provided by investing activities	39,494	5,405,435
Cash Flows From Financing Activities:
Principal payments on financing agreements with mark-to-market collateral provisions	(698,220)	(21,021,793)
Proceeds from borrowings under financing agreements with mark-to-market collateral provisions	721,380	13,537,087
Principal payments on other collateralized financing agreements	(1,072,865)	(57,404)
Proceeds from borrowings under other collateralized financing agreements	1,243,860	2,517,556
Payment made for other collateralized financing agreement related costs	(5,119)	0
Principal payment on redemption of Senior notes	(100,000)	0
Payments made for settlements and unwinds of Swaps	0	(88,405)
Proceeds from issuance of series C preferred stock	0	275,000
Payments made for costs related to series C preferred stock issuance	0	(8,948)
Proceeds from issuances of common stock	772	724
Proceeds from the issuance of warrants	0	14,041
Payments made for the repurchase of common stock through the share repurchase program	(48,075)	0
Dividends paid on preferred stock	(16,438)	0
Dividends paid on common stock and dividend equivalents	(67,656)	(90,749)
Net cash used in financing activities	(42,361)	(4,922,891)
Net increase in cash, cash equivalents and restricted cash	93,729	539,188
Cash, cash equivalents and restricted cash at beginning of period	821,519	134,664
Cash, cash equivalents and restricted cash at end of period	915,248	673,852
Supplemental Disclosure of Cash Flow Information
Interest Paid	58,610	165,333
Non-cash Investing and Financing Activities:
Transfer from residential whole loans to real estate owned	38,370	59,219
Dividends and dividend equivalents declared and unpaid	44,236	0
Payable for unsettled residential whole loan purchases	131,275	0
Right-of-use lease asset and lease liability	$ 40,893	$ 0