CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash Flows From Operating Activities:
Net income/(loss)	$ 85,522	$ (908,995)
Adjustments to reconcile net income to net cash provided by operating activities:
(Gains)/losses on residential whole loans and real estate owned, net	(35,893)	217,920
(Gains)/losses on securities, net	(100)	170,550
Impairment and other losses on securities available-for-sale and other assets	0	419,651
Accretion of purchase discounts on residential whole loans and securities	(16,436)	(12,114)
Amortization of purchase premiums on residential whole loans and securities, and amortization of terminated hedging instruments	6,791	15,266
(Reversal of provision)/provision for credit and valuation losses on residential whole loans and other financial instruments	(23,967)	150,711
Net other non-cash losses included in net income	5,212	7,689
Increase in other assets	(1,939)	(37,811)
Increase/(decrease) in other liabilities	4,975	(9,653)
Net cash provided by operating activities	24,165	13,214
Cash Flows From Investing Activities:
Purchases of residential whole loans, loan related investments and capitalized advances	(184,707)	(1,119,464)
Principal payments on residential whole loans and loan related investments	425,300	508,855
Principal payments on securities	58,896	539,882
Proceeds from sales of securities and other assets	0	1,009,316
Purchases of securities	0	(162,607)
Purchases of real estate owned and capital improvements	(217)	(5,606)
Proceeds from sales of real estate owned	50,619	52,042
Additions to leasehold improvements, furniture and fixtures	(4,415)	(176)
Net cash provided by investing activities	345,476	822,242
Cash Flows From Financing Activities:
Principal payments on financing agreements with mark-to-market collateral provisions	(821,716)	(12,903,818)
Proceeds from borrowings under financing agreements with mark-to-market collateral provisions	663,926	12,216,862
Principal payments on other collateralized financing agreements	(521,259)	(37,418)
Proceeds from borrowings under other collateralized financing agreements	437,915	0
Payment made for other collateralized financing agreement related costs	(1,371)	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	(8,912)
Proceeds from issuances of common stock	376	687
Payments made for the repurchase of common stock through the share repurchase program	(20,933)	0
Dividends paid on preferred stock	(8,219)	0
Dividends paid on common stock and dividend equivalents	(34,015)	(90,749)
Net cash used in financing activities	(405,296)	(636,753)
Net (decrease)/increase in cash, cash equivalents and restricted cash	(35,655)	198,703
Cash, cash equivalents and restricted cash at beginning of period	821,519	134,664
Cash, cash equivalents and restricted cash at end of period	785,864	333,367
Supplemental Disclosure of Cash Flow Information
Interest Paid	29,554	80,158
Non-cash Investing and Financing Activities:
Transfer from residential whole loans to real estate owned	20,068	50,693
Dividends and dividend equivalents declared and unpaid	33,640	0
Payable for unsettled residential whole loan purchases	112,202	0
Receivable for unsettled residential whole loan and securities sales	$ 0	$ 419,583