Statements of Income (USD $) In Thousands, except Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Interest income:
Interest income on mortgage-backed securities	$ 113,188	$ 63,441	$ 200,123	$ 132,382
Interest income on short-term cash investments	331	298	671	575
Interest income	113,519	63,739	200,794	132,957
Interest expense	35,910	23,677	62,104	47,117
Net interest income	77,609	40,062	138,690	85,840
Other income:
Gain on sale of mortgage-backed securities	4,405		4,405	1,044
Operating expenses:
Management fee	3,531	2,196	6,623	4,379
Share based compensation	194	347	401	690
General and administrative	746	707	1,305	1,269
Total operating expenses	4,471	3,250	8,329	6,338
Net income	$ 77,543	$ 36,812	$ 134,766	$ 80,546
Earnings per share - common stock, basic	$ 1.04	$ 1.01	$ 2.01	$ 2.21
Earnings per share - common stock, diluted	$ 1.04	$ 1.01	$ 2.01	$ 2.21
Dividends per share	$ 1.00	$ 1.10	$ 2.00	$ 2.30
Weighted average shares outstanding	74,807,174	36,609,290	67,167,275	36,426,572