Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Operating activities:
Net income	$ 53,675	$ 25,406
Adjustments to reconcile net income to cash provided by operating activities:
Increase in accrued interest receivable	(9,383)	(6,248)
(Decrease) increase in accrued interest payable	216	161
Provision for loan losses	170	750
Gain on sale of investments, net	(6,418)	(1,323)
Loss on non-recourse collateralized financing	0	1,970
Fair value adjustments, net	129	657
Increase in litigation settlement and related costs reserve	0	7,861
Amortization and depreciation	58,999	22,312
Stock-based compensation expense	1,410	492
Cash paid for stock appreciation rights	(116)	0
Net change in other assets and other liabilities	(2,348)	1,564
Net cash and cash equivalents provided by operating activities	96,334	53,602
Investing activities:
Purchase of investments	(2,454,851)	(1,440,594)
Principal payments received on investments	34,038	344,649
Increase in principal receivable on investments	(6,548)	(6,566)
Proceeds from sales of investments	185,485	124,797
Principal payments received on securitized mortgage loans	459,380	32,655
Other investing activities	(3,001)	77
Net cash and cash equivalents used in investing activities	(1,785,497)	(944,982)
Financing activities:
Borrowings under repurchase agreements, net	1,577,943	819,503
Deferred borrowing costs paid	(825)	0
Principal payments on non-recourse collateralized financing	(39,773)	(2,094)
Proceeds from issuance of preferred stock	55,407	0
Proceeds from issuance of stock	123,832	95,261
Dividends paid	(41,474)	(29,970)
Net cash and cash equivalents provided by financing activities	1,675,110	882,700
Net increase in cash and cash equivalents	(14,053)	(8,680)
Cash and cash equivalents at beginning of period	48,776	18,836
Cash and cash equivalents at end of period	34,723	10,156
Supplemental Disclosure of Cash Activities:
Cash paid for interest	$ 24,284	$ 16,411