Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Operating activities:
Net (loss) income	$ (734)	$ 19,603
Adjustments to reconcile net income to cash provided by operating activities:
Decrease (increase) in accrued interest receivable	1,684	1,401
(Decrease) increase in accrued interest payable	298	(22)
Provision for loan losses	0	261
Loss on derivative instruments, net	(13,422)	(17)
Loss (gain) on sale of investments, net	(3,307)	1,391
Fair value adjustments, net	32	(140)
Amortization and depreciation	34,829	32,117
Stock-based compensation expense	672	481
Other operating activities	175	4,400
Net cash and cash equivalents provided by operating activities	49,903	45,405
Investing activities:
Purchase of investments	127,552	438,376
Principal payments received on investments	128,676	215,751
Proceeds from sales of investments	59,799	31,158
Principal payments received on mortgage loans held for investment, net	1,605	5,737
Net payments on derivatives not designated as hedges	2,542	174
Other investing activities	5	827
Net cash and cash equivalents used in investing activities	59,981	(186,731)
Financing activities:
(Repayments of) borrowings under repurchase agreements, net	(95,314)	144,023
Principal payments on non-recourse collateralized financing	(527)	(2,024)
Increase in restricted cash	4,857	0
Proceeds from issuance of common stock	114	5,152
Payments Related to tax withholding for share-based compensation	505	545
Dividends paid	16,957	16,960
Net cash and cash equivalents provided by (used in) financing activities	(118,046)	129,646
Net increase (decrease) in cash and cash equivalents	(8,162)	(11,680)
Cash and cash equivalents at beginning of period	69,330	55,809
Cash and cash equivalents at end of period	61,168	44,129
Supplemental Disclosure of Cash Activities:
Cash paid for interest	$ 4,935	$ 10,381