Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating activities:
Net income (loss)	$ 11,931	$ (25,962)
Adjustments to reconcile net income (loss) to cash provided by operating activities:
Decrease in accrued interest receivable	1,129	3,263
(Decrease) increase in accrued interest payable	(436)	420
Loss on derivative instruments, net	9,634	62,153
Loss on sale of investments, net	(10,628)	(4,238)
Fair value adjustments, net	(63)	(86)
Amortization of investment premiums, net	122,621	112,418
Other amortization and depreciation, net	983	1,186
Stock-based compensation expense	1,567	2,066
Increase in other assets and liabilities, net	(1,905)	(2,060)
Net cash and cash equivalents provided by operating activities	156,089	157,636
Investing activities:
Purchase of investments	(772,590)	(96,816)
Principal payments received on investments	248,298	337,719
Proceeds from sales of investments	792,984	94,033
Principal payments received on mortgage loans held for investment, net	2,641	3,709
Distributions received from limited partnership	0	10,835
Net receipts (payments) on derivatives, including terminations	11,743	(24,483)
Other investing activities	(214)	(105)
Net cash and cash equivalents provided by investing activities	282,862	324,892
Financing activities:
Borrowings under repurchase agreements	60,229,426	19,293,243
Repayments of repurchase agreement borrowings and FHLB advances	(60,609,148)	(19,661,384)
Principal payments on non-recourse collateralized financing	(747)	(1,443)
Proceeds from issuance of preferred stock	25,884	0
Proceeds from issuance of common stock	14,495	102
Cash paid for stock issuance costs	(61)	0
Cash paid for repurchases of common stock	0	(310)
Payments related to tax withholding for stock-based compensation	(521)	(485)
Dividends paid	(35,479)	(39,285)
Net cash and cash equivalents used in financing activities	(376,151)	(409,562)
Net increase in cash, cash equivalents, and restricted cash	62,800	72,966
Cash, cash equivalents, and restricted cash at beginning of period	98,889	85,125
Cash, cash equivalents, and restricted cash at end of period	161,689	158,091
Supplemental Disclosure of Cash Activity:
Cash paid for interest	$ 26,766	$ 18,185