CONSOLIDATED BALANCE SHEETS (UNAUDITED) (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified			6 Months Ended
	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2014 Redeemable Preferred Stock [Member] Cumulative Redeemable Preferred Stock, Series E [Member]	Dec. 31, 2013 Redeemable Preferred Stock [Member] Cumulative Redeemable Preferred Stock, Series E [Member]
Residential mortgage investments	$ 13,440,000	$ 13,120,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	250,000	250,000
Common stock, shares issued (in shares)	95,767	95,807
Common stock, shares outstanding (in shares)	95,767	95,807
Preferred stock, shares authorized (in shares)	100,000	100,000
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred stock, shares issued (in shares)			7,438	6,861
Preferred stock, shares outstanding (in shares)			7,438	6,861
Preferred stock, aggregate liquidation preference			$ 185,961	$ 171,521
Preferred stock, dividend rate (in hundredths)			7.50%