Relationship with Bayview Lending Group LLC and Bayview Financial Holdings, L.P. (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Relationship with Bayview Lending Group LLC and Bayview Financial Holdings, L.P. (Textual) [Abstract]
Minority interest in Bayview Lending Group LLC			20.00%
Carrying value of minority interest investment in Bayview Lending Group LLC	$ 199,000,000		$ 199,000,000
Outstanding principal balances of commercial mortgage loans from BLG and Bayview Financial	4,700,000,000		4,700,000,000		5,200,000,000
Amounts recorded as capitalized servicing assets for commercial mortgage loans	18,000,000		18,000,000		26,000,000
Servicing rights purchased from Bayview Financial related to residential mortgage loans	6,000,000		6,000,000		9,000,000
Outstanding principal balances of residential mortgage loans from Bayview Financial	3,300,000,000		3,300,000,000		3,600,000,000
Revenues from servicing residential and small balance commercial mortgage loans	10,000,000	11,000,000	31,000,000	35,000,000
Collateralized mortgage obligations in available-for-sale investment securities portfolio securitized by Bayview Financial	17,000,000		17,000,000		22,000,000
Investment securities in held-to-maturity portfolio securitized by Bayview Financial	$ 278,000,000		$ 278,000,000		$ 313,000,000