Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Operating activities:
Net income	$ 46,510	$ 54,489
Adjustments to reconcile net income to cash provided by operating activities:
Increase in accrued interest receivable	906	(9,383)
Decrease in accrued interest payable	(462)	216
Provision for loan losses	261	170
Loss on derivative instruments, net	12,683	907
Gain on sale of investments, net	(2,597)	(6,418)
Fair value adjustments, net	590	(778)
Amortization and depreciation	102,258	58,999
Stock-based compensation expense	1,762	1,294
Net change in other assets and other liabilities	(3,907)	(2,347)
Net cash and cash equivalents provided by operating activities	158,004	97,149
Investing activities:
Purchase of investments	(1,325,082)	(2,454,851)
Principal payments received on investments	743,810	459,380
(Increase) decrease in principal receivable on investments	(1,259)	(6,548)
Proceeds from sales of investments	327,962	185,485
Principal payments received on securitized mortgage loans	10,775	34,038
Net payments on derivatives not designated as hedges	(23,644)	0
Other investing activities	5,402	(3,001)
Net cash and cash equivalents used in investing activities	(262,036)	(1,785,497)
Financing activities:
Borrowings under repurchase agreements, net	110,409	1,577,943
Deferred borrowing costs paid	0	(825)
Principal payments on non-recourse collateralized financing	(9,502)	(39,773)
Increase in restricted cash	(15,849)	0
Proceeds from issuance of preferred stock	54,251	55,407
Proceeds from issuance of common stock	7,375	123,832
Cash paid for repurchases of common stock	(5,965)	0
Payments Related to Tax Withholding for Share-based Compensation	(545)	0
Dividends paid	(52,343)	(42,289)
Net cash and cash equivalents provided by financing activities	87,831	1,674,295
Net increase in cash and cash equivalents	(16,201)	(14,053)
Cash and cash equivalents at beginning of period	55,809	48,776
Cash and cash equivalents at end of period	39,608	34,723
Supplemental Disclosure of Cash Activities:
Cash paid for interest	$ 22,065	$ 24,284