Consolidated Statements of Income (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Interest income:
Interest income on mortgage-backed securities	$ 124,241	$ 112,759
Interest income on short-term cash investments	442	333
Total interest income	124,683	113,092
Interest expense	53,277	41,109
Net interest income	71,406	71,983
Operating expenses:
Management Fee	4,720	3,842
Share based compensation	629	429
General and administrative	1,369	913
Total operating expenses	6,718	5,184
Other income:
Net gain on sale of mortgage-backed securities	2,500	2,505
Net gain on futures contracts	51
Total other income	2,551	2,505
Net income	67,239	69,304
Dividends on preferred stock	5,480	0
Net income available to common shareholders	$ 61,759	$ 69,304
Earnings per share - common stock, basic	$ 0.62	$ 0.89
Earnings per share - common stock, diluted	$ 0.62	$ 0.89
Dividends per share of common stock	$ 0.70	$ 0.90
Weighted average common shares outstanding, basic	98,827,587	77,610,117
Weighted average common shares outstanding, diluted	98,827,587	77,610,117