CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2012		Sep. 30, 2011		Sep. 30, 2012		Sep. 30, 2011
Interest income:
Investments	$ 754,096		$ 926,558		$ 2,481,284		$ 2,713,141
U.S. Treasury Securities	4,588		2,302		13,403		13,624
Securities loaned	2,581		1,942		7,797		5,153
Total interest income	761,265		930,802		2,502,484		2,731,918
Interest expense:
Repurchase agreements	158,150		109,014		411,643		311,780
Convertible Senior Notes	18,026		8,798		51,718		22,465
U.S. Treasury Securities sold, not yet purchased	3,739		2,109		12,184		11,867
Securities borrowed	1,978		1,496		6,136		4,081
Total interest expense	181,893		121,417		481,681		350,193
Net interest income	579,372		809,385		2,020,803		2,381,725
Other income (loss):
Investment advisory and other fee income	21,034		20,828		63,729		58,745
Net gains (losses) on disposition of investments	142,172		91,668		317,308		126,189
Net loss on extinguishment of Convertible Senior Notes	(87,328)				(87,328)
Dividend income from affiliates	7,097		8,706		21,239		23,233
Net gains (losses) on trading assets	1,368		1,942		7,729		15,042
Net unrealized gain (losses) on interest-only Agencymortgage-backed securities	(33,563)		(39,321)		(28,789)		(39,045)
Income from underwriting			2,772				5,599
Subtotal	50,780		86,595		293,888		189,763
Realized gains (losses) on interest rate swaps	(224,272)	[1],[2]	(231,849)	[1],[2]	(665,614)	[1],[2]	(654,757)	[1],[2]
Realized gains (losses) on termination of interest rate swaps					(2,385)
Unrealized gains (losses) on interest rate swaps	(104,197)		(1,505,333)		(373,773)		(1,802,968)
Subtotal	(328,469)		(1,737,182)		(1,041,772)		(2,457,725)
Total other income (loss)	(277,689)		(1,650,587)		(747,884)		(2,267,962)
Expenses:
Compensation expense	52,310		57,629		164,860		151,911
Other general and administrative expenses	10,694		7,565		30,615		22,339
Total expenses	63,004		65,194		195,475		174,250
Income (loss) before income taxes and income from equity method investment in affiliate	238,679		(906,396)		1,077,444		(60,487)
Income taxes	(13,921)		(15,417)		(42,039)		(41,754)
Income from equity method investment in affiliate							1,140
Net income (loss)	224,758		(921,813)		1,035,405		(101,101)
Dividends on preferred stock	9,367		4,172		19,813		12,706
Net income (loss) available (related) to common shareholders	215,391		(925,985)		1,015,592		(113,807)
Net income (loss) available (related) per share to common shareholders:
Basic	$ 0.22		$ (0.98)		$ 1.04		$ (0.14)
Diluted	$ 0.22		$ (0.98)		$ 1.00		$ (0.14)
Weighted average number of common shares outstanding:
Basic	974,729,078		948,545,975		973,674,586		841,912,810
Diluted	997,007,829		948,545,975		1,035,365,251		841,912,810
Dividends Declared Per Share of Common Stock	$ 0.50		$ 0.60		$ 1.60		$ 1.87
Net income (loss)	224,758		(921,813)		1,035,405		(101,101)
Other comprehensive income (loss):
Unrealized gains (losses) on available-for-sale securities	798,269		1,115,325		1,377,737		2,020,737
Unrealized losses on interest rate swaps							14,298
Reclassification adjustment for net (gains) losses included in net income (loss)	(141,982)		(91,668)		(317,118)		(126,189)
Other comprehensive income (loss)	656,287		1,023,657		1,060,619		1,908,846
Comprehensive income (loss)	$ 881,045		$ 101,844		$ 2,096,024		$ 1,807,745

[1] Interest expense related to the Company's interest rate swaps is recorded in Realized gains losses on interest rate swaps on the Consolidated Statements of Operations and Comprehensive Income (Loss).

[2] Net interest payments on interest rate swaps is presented in the Company's Consolidated Statements of Comprehensive Income as realized gains (losses) on interest rate swaps.