CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Operating activities
Net income (loss)	$ 18,942	$ (204,653)
Adjustments to reconcile net income (loss) to cash provided by operating activities:
Amortization of investment premiums	20,887	20,691
Amortization of equity-based awards	706	835
Amortization of unrealized loss (gain) on de-designated hedges	646	(103)
Loss on sale of mortgage investments		67,820
(Gain) loss on derivative instruments (net)	(2,228)	156,747
Other depreciation and amortization	30	29
Net change in receivables, other assets, accounts payable and accrued expenses	2,394	(1,872)
Net cash provided by operating activities	41,377	39,494
Investing activities
Purchases of residential mortgage investments	(404,224)	(814,547)
Proceeds from sales of residential mortgage investments		2,540,426
Interest receivable acquired with the purchase of residential mortgage investments	(652)	(1,495)
Principal collections on residential mortgage investments, including changes in mortgage securities principal remittance receivable	884,482	902,873
Net cash provided by investing activities	479,606	2,627,257
Financing activities
Proceeds from repurchase arrangements and similar borrowings	13,609,509	29,271,292
Principal payments on repurchase arrangements and similar borrowings	(14,123,531)	(31,167,283)
Decrease (increase) in cash collateral receivable from derivative counterparties	12,615	(30,452)
Increase in cash collateral receivable from secured borrowing counterparties		(359,168)
Net receipts from (payments on) derivative settlements	2,125	(150,760)
Issuance of common stock		12,882
Other capital stock transactions	(104)	(107)
Dividends paid	(19,544)	(19,104)
Net cash used in financing activities	(518,930)	(2,442,700)
Net change in cash and cash equivalents	2,053	224,051
Cash and cash equivalents at beginning of period	257,180	105,397
Cash and cash equivalents at end of period	$ 259,233	$ 329,448