Consolidated Statements of Income (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Interest income:
Interest income on mortgage-backed securities	$ 107,040	$ 131,940	$ 346,396	$ 373,420
Interest income on short-term cash investments	303	387	1,104	1,160
Total interest income	107,343	132,327	347,500	374,580
Interest expense	51,599	52,767	156,955	140,045
Net interest income	55,744	79,560	190,545	234,535
Operating expenses:
Management fee	4,522	4,557	13,956	12,711
Share based compensation	637	447	1,893	1,301
General and administrative	1,538	1,040	4,509	3,269
Total operating expenses	6,697	6,044	20,358	17,281
Other income (loss):
Net realized gain (loss) on sale of mortgage-backed securities	(225,635)	10,534	(214,333)	25,244
Impairment of mortgage-backed securities	(8,102)		(8,102)
Net realized loss on futures contracts	(27,327)		(27,327)
Net unrealized loss on futures contracts	(50,129)		(44,593)
Total other income (loss)	(311,193)	10,534	(294,355)	25,244
Net income (loss)	(262,146)	84,050	(124,168)	242,498
Dividends on preferred stock	5,481	2,070	16,441	2,070
Net income (loss) available to common shareholders	$ (267,627)	$ 81,980	$ (140,609)	$ 240,428
Earnings (loss) per share - common stock, basic	$ (2.72)	$ 0.83	$ (1.43)	$ 2.63
Earnings (loss) per share - common stock, diluted	$ (2.72)	$ 0.83	$ (1.43)	$ 2.63
Dividends per share of common stock	$ 0.55	$ 0.80	$ 1.95	$ 2.60
Weighted average common shares outstanding, basic	98,318,205	98,233,589	98,656,750	91,296,338
Weighted average common shares outstanding, diluted	98,318,205	98,233,589	98,656,750	91,296,338