CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash Flows From Operating Activities:
Net income/(loss)	$ 284,747	$ (725,207)
Adjustments to reconcile net income to net cash provided by operating activities:
(Gains)/losses on residential whole loans and real estate owned, net	(67,844)	280,142
Gains on securities, net	(1,969)	(71,569)
Impairment and other gains and losses on securities available-for-sale and other assets	(49,039)	424,966
Loss on terminated swaps previously designed as hedges for accounting purposes	0	57,034
Accretion of purchase discounts and amortization of purchase premiums on residential whole loans and securities, and amortization of terminated hedging instruments	(23,295)	13,367
(Reversal of provision)/provision for credit and valuation losses on residential whole loans and other financial instruments	(43,550)	38,090
Net other non-cash losses included in net income	16,112	16,388
Decrease in other assets	20,484	459
Decrease in other liabilities	(26,574)	(16,919)
Net cash provided by operating activities	109,072	16,751
Cash Flows From Investing Activities:
Purchases of residential whole loans, loan related investments and capitalized advances	(2,877,090)	(1,345,422)
Proceeds from sales of residential whole loans, and residential whole loan repurchases	0	1,521,060
Principal payments on residential whole loans and loan related investments	1,433,199	1,261,319
Increase in cash balances resulting from Lima One purchase transaction, net	6,122	0
Purchases of securities	0	(163,748)
Proceeds from sales of securities and other assets	0	3,790,148
Principal payments on securities	130,686	609,758
Purchases of real estate owned and capital improvements	(1,087)	(9,334)
Proceeds from sales of real estate owned	133,157	203,603
Additions to leasehold improvements, furniture and fixtures	(50,735)	(1,425)
Net cash (used in)/provided by investing activities	(1,225,748)	5,865,959
Cash Flows From Financing Activities:
Principal payments on financing agreements with mark-to-market collateral provisions	(941,468)	(21,401,578)
Proceeds from borrowings under financing agreements with mark-to-market collateral provisions	2,009,691	13,749,720
Principal payments on other collateralized financing agreements	(1,484,127)	(464,838)
Proceeds from borrowings under other collateralized financing agreements	1,582,982	2,908,710
Payment made for other collateralized financing agreement related costs	(6,847)	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	1,297	725
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	(24,656)	(21,578)
Dividends paid on common stock and dividend equivalents	(111,892)	(90,749)
Net cash provided by/(used in) financing activities	876,905	(5,127,900)
Net (decrease)/increase in cash, cash equivalents and restricted cash	(239,771)	754,810
Cash, cash equivalents and restricted cash at beginning of period	821,519	134,664
Cash, cash equivalents and restricted cash at end of period	581,748	889,474
Supplemental Disclosure of Cash Flow Information
Interest Paid	81,636	213,318
Non-cash Investing and Financing Activities:
Transfer from residential whole loans to real estate owned	50,043	74,891
Dividends and dividend equivalents declared and unpaid	44,247	22,758
Payable for unsettled residential whole loan purchases	163,015	0
Right-of-use lease asset and lease liability	40,893	0
Repayment of Lima One preferred stock in connection with the Lima One transaction (see Note 16)	$ 22,030	$ 0