SECURITIZATIONS AND VARIABLE INTEREST ENTITIES (Details 7) (USD $)			3 Months Ended					3 Months Ended
	Mar. 31, 2013	Dec. 31, 2012	Mar. 31, 2013 Mortgage servicing rights	Mar. 31, 2012 Mortgage servicing rights	Mar. 31, 2013 Non-agency-sponsored mortgages	Mar. 31, 2013 Senior interests	Mar. 31, 2013 Subordinated interests	Mar. 31, 2013 U.S. government-sponsored agency guaranteed
Classification of Securitizations
Fair value of capitalized mortgage servicing rights			$ 2,200,000,000	$ 2,700,000,000
Principal amount of loans and other financial instruments			311,000,000,000	387,000,000,000
Re-securitizations
Balance at beginning of period	2,203,000,000	1,942,000,000	1,942,000,000	2,569,000,000
Originations			172,000,000	144,000,000
Changes in fair value of MSRs due to changes in inputs and assumptions			223,000,000	249,000,000
Other changes			(133,000,000)	(271,000,000)
Sale of MSRs			(1,000,000)
Balance at end of period	2,203,000,000	1,942,000,000	2,203,000,000	2,691,000,000
Servicing fees			217,000,000	268,000,000
Late fees			8,000,000	17,000,000
Ancillary fees			31,000,000	28,000,000
Total MSR fees			256,000,000	313,000,000
Original par value of securities transferred to re-securitization entities					244,000,000
Original par value of re-securitizations deals in which the entity holds a retained interest					6,600,000,000
Fair value of re-securitizations deals in which the entity holds a retained interest					374,000,000	17,000,000	357,000,000	1,900,000,000
Market value of retained interest related to re-securitization transaction in 2013					32,000,000			1,000,000,000
Original fair value of re-securitizations deals in which the entity holds a retained interest								73,100,000,000
Securities transferred to re-securitization entities								$ 7,400,000,000