Consolidated Statements Of Income (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Interest income:
Mortgage securities and similar investments	$ 63,136	$ 47,634	$ 116,277	$ 107,784
Other	58	135	171	227
Interest income, operating, total	63,194	47,769	116,448	108,011
Interest expense:
Repurchase arrangements and similar borrowings	(13,706)	(11,146)	(26,028)	(24,514)
Unsecured borrowings	(2,187)	(2,187)	(4,374)	(4,374)
Other	(1)		(5)
Interest expense	(15,894)	(13,333)	(30,407)	(28,888)
Net interest income (expense)	47,300	34,436	86,041	79,123
Other revenue (expense):
Miscellaneous other revenue (expense)	(599)	(98)	(817)	(303)
Incentive compensation	(1,487)	(1,330)	(2,720)	(2,745)
Salaries and benefits	(1,672)	(1,463)	(3,373)	(3,106)
Other general and administrative expense	(1,066)	(1,851)	(2,028)	(2,903)
Operating expenses	(4,824)	(4,742)	(8,938)	(9,057)
Income before equity in earnings of unconsolidated affiliates	42,476	29,694	77,103	70,066
Equity in earnings of unconsolidated affiliates	65	65	130	130
Net income	42,541	29,759	77,233	70,196
Net income available to common stockholders:
Net income	42,541	29,759	77,233	70,196
Less cash dividends paid on preferred shares	(5,060)	(5,059)	(10,118)	(10,117)
Net income (loss) available to common stockholders, basic, total	$ 37,481	$ 24,700	$ 67,115	$ 60,079
Net income per common share:
Basic	$ 0.48	$ 0.35	$ 0.90	$ 0.86
Diluted	$ 0.48	$ 0.35	$ 0.90	$ 0.86
Cash dividends declared per share:
Common	$ 0.480	$ 0.360	$ 0.890	$ 0.860
Series A Preferred	$ 0.400	$ 0.400	$ 0.800	$ 0.800
Series B Preferred	$ 0.315	$ 0.315	$ 0.630	$ 0.630