CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net income (loss)	$ 1,327,704	$ 440,408
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Amortization of premiums and discounts of investments, net	92,976	201,590
Amortization of securitized debt premiums and discounts and deferred financing costs	408	340
Depreciation, amortization and other noncash expenses	5,822	7,006
Net (gains) losses on disposals of investments	(13,468)	(5,235)
Net (gains) losses on investments and derivatives	(878,547)	(173,186)
Income from unconsolidated joint ventures	618	1,031
Payments on purchases of loans held for sale	(37,190)	(54,234)
Proceeds of sales and repayments of loans held for sale	30,178	144,890
Net payments on derivatives	951,021	(738,872)
Net change in:
Other assets	(42,361)	(52,903)
Accrued interest and dividends receivable	(2,963)	3,294
Accrued interest payable	31,628	19,465
Accounts payable and other liabilities	(132,910)	(15,995)
Net cash provided by (used in) operating activities	1,332,916	(222,401)
Cash flows from investing activities:
Payments on purchases of Residential Investment Securities	(3,718,947)	(2,043,364)
Proceeds from sales of Residential Investment Securities	463,214	1,787,574
Principal payments on Residential Investment Securities	2,696,245	2,952,739
Purchase of MSRs	(249)	(7,210)
Payments on purchases of corporate debt	(230,103)	(91,749)
Principal payments on corporate debt	92,820	44,418
Originations and purchases of commercial real estate related assets	(91,647)	(142,738)
Proceeds from sales on commercial real estate related assets	9,556	11,960
Principal repayments on commercial real estate related assets	130,555	370,689
Proceeds from reverse repurchase agreements	20,050,112	21,015,000
Payments on reverse repurchase agreements	(20,250,571)	(21,015,000)
Distributions in excess of cumulative earnings from unconsolidated joint ventures	2,813	2,042
Payments on purchases of residential mortgage loans held for investment	(167,124)	(375,367)
Proceeds from repayments from residential mortgage loans held for investment	67,384	28,308
Payments on purchases of equity securities	0	(2,104)
Net cash provided by (used in) investing activities	(945,942)	2,535,198
Cash flows from financing activities:
Proceeds from repurchase agreements and other secured financing	1,299,589,620	783,704,227
Principal payments on repurchase agreements and other secured financing	(1,299,277,944)	(786,209,502)
Proceeds from issuance of securitized debt	279,203	0
Principal repayments on securitized debt	(317,773)	(197,749)
Payment of deferred financing cost	0	(1,079)
Net proceeds from stock offerings, direct purchases and dividend reinvestments	412,081	596
Redemption of preferred stock	(412,500)	0
Principal payments on participation sold	0	(84)
Principal payments on mortgages payable	0	(18)
Net contributions/(distributions) from/(to) noncontrolling interests	(333)	(366)
Dividends paid	(381,642)	(329,147)
Net cash provided by (used in) financing activities	(109,288)	(3,033,122)
Net (decrease) increase in cash and cash equivalents	277,686	(720,325)
Cash and cash equivalents including cash pledged as collateral, beginning of period	706,589	1,539,746
Cash and cash equivalents including cash pledged as collateral, end of period	984,275	819,421
Supplemental disclosure of cash flow information:
Interest received	1,017,534	787,971
Interest paid (excluding interest paid on interest rate swaps)	320,988	223,109
Net interest paid on interest rate swaps	39,206	77,192
Taxes paid	2	0
Noncash investing activities:
Receivable for investments sold	45,126	354,126
Payable for investments purchased	91,327	340,383
Net change in unrealized gains (losses) on available-for-sale securities, net of reclassification adjustment	(1,874,060)	(40,198)
Noncash financing activities:
Dividends declared, not yet paid	$ 347,897	$ 305,691