Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Operating activities:
Net (loss) income	$ (40,662)	$ 20,990
Adjustments to reconcile net (loss) income to cash provided by operating activities:
Decrease (increase) in accrued interest receivable	3,145	(158)
(Decrease) increase in accrued interest payable	(29)	120
Loss on derivative instruments, net	64,561	8,233
Loss on sale of investments, net	4,238	183
Fair value adjustments, net	(51)	(59)
Amortization of investment premiums, net	73,597	74,737
Other amortization and depreciation, net	850	2,847
Stock-based compensation expense	1,443	1,475
Other operating activities	(862)	18
Net cash and cash equivalents provided by operating activities	106,230	108,386
Investing activities:
Purchase of investments	(4,970)	(1,000,070)
Principal payments received on investments	187,437	236,598
Proceeds from sales of investments	94,033	233,238
Principal payments received on mortgage loans held for investment, net	2,319	9,825
Payment to acquire interest in limited partnership	0	(6,000)
Distributions received from limited partnership	10,835	0
Net payments on derivatives, including terminations	(26,092)	(10,968)
Other investing activities	(55)	(135)
Net cash and cash equivalents provided by (used in) investing activities	263,507	(537,512)
Financing activities:
Borrowings under repurchase agreements and FHLB advances	11,394,652	9,719,787
Repayments of repurchase agreement borrowings and FHLB advances	(11,640,592)	(9,221,857)
Principal payments on non-recourse collateralized financing	(939)	(2,035)
Increase in restricted cash	(32,489)	(15,617)
Proceeds from issuance of common stock, net of issuance costs	58	59
Payments related to tax withholding for stock-based compensation	(310)	(6,688)
Payments related to tax withholding for stock-based compensation	(485)	(557)
Dividends paid	(26,670)	(31,447)
Net cash and cash equivalents (used in) provided by financing activities	(306,775)	441,645
Net increase in cash and cash equivalents	62,962	12,519
Cash and cash equivalents at beginning of period	33,935	43,944
Cash and cash equivalents at end of period	96,897	56,463
Supplemental Disclosure of Cash Activities:
Cash paid for interest	$ 12,476	$ 8,842