Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Assets
Mortgage-backed securities, at fair value (including pledged assets of $15,897,380 and $17,049,670 at March 31, 2014 and December 31,2013, respectively)	$ 17,137,956	$ 17,642,532
Cash and cash equivalents	250,258	763,326
Restricted cash	231,591	225,379
Unsettled purchased mortgage-backed securities, at fair value	157,201
Receivable for securities sold		231,214
Accrued interest receivable	53,629	55,156
Principal payments receivable	70,524	95,021
Debt security, held to maturity, at cost	15,000	15,000
Interest rate swap asset	12,703	15,841
Other assets	36,393	33,891
Total assets	17,965,255	19,077,360
Liabilities and shareholders’ equity
Repurchase agreements	15,183,457	16,129,683
Dollar roll liability		351,826
Payable for unsettled securities	157,387
Accrued interest payable	3,475	8,279
Interest rate swap liability	106,132	125,133
Futures contract liability	48,584	36,733
Dividend payable	52,885	52,929
Accounts payable and other liabilities	20,621	8,676
Total liabilities	15,572,541	16,713,259
Shareholders’ equity:
7.625% Series A Cumulative Redeemable Preferred stock, $.001 par value, 25,000,000 shares authorized, 11,500,000 shares issued and outstanding at March 31, 2014 and December 31, 2013, respectively ($287,500 aggregate liquidation preference)	278,252	278,252
Common stock, $.001 par value, 200,000,000 shares authorized, 96,601,523 and 98,822,654 shares issued and outstanding at December 31, 2013 and December 31, 2012, respectively	97	97
Additional paid-in capital	2,451,966	2,453,018
Accumulated deficit	(396,154)	(359,214)
Accumulated other comprehensive income (loss)	58,553	(8,052)
Total shareholders’ equity	2,392,714	2,364,101
Total liabilities and shareholders’ equity	$ 17,965,255	$ 19,077,360