Commitments, Contingent Liabilities and Guarantees (Details) (USD $) In Millions, unless otherwise specified					12 Months Ended			12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Standby letters of credit [Member]	Dec. 31, 2011 Recourse agreement with FNMA [Member]	Dec. 31, 2011 Return guarantee agreement with LIHTC investors [Member]	Dec. 31, 2011 Written put options [Member]	Dec. 31, 2011 Default guarantees [Member]	Dec. 31, 2011 Maximum [Member] Risk Level, Low [Member]	Dec. 31, 2011 Maximum [Member] Risk Level, Medium [Member]	Dec. 31, 2011 Maximum [Member] Risk Level, High [Member]	Dec. 31, 2011 Minimum [Member] Risk Level, Low [Member]	Dec. 31, 2011 Minimum [Member] Risk Level, Medium [Member]	Dec. 31, 2011 Minimum [Member] Risk Level, High [Member]	Dec. 31, 2011 Commercial and other [Member]	Dec. 31, 2010 Commercial and other [Member]	Dec. 31, 2011 Home equity [Member]	Dec. 31, 2010 Home equity [Member]	Dec. 31, 2011 Commercial real estate and construction [Member]	Dec. 31, 2010 Commercial real estate and construction [Member]
Commitments to extend credit or funding
Total loan commitments	$ 28,435	$ 27,237												$ 19,813	$ 18,523	$ 7,366	$ 7,656	$ 1,256	$ 1,058
When issued and to be announced securities commitments	117	177
Commercial letters of credit	124	96
Principal investing commitments	123	200
Liabilities of certain limited partnerships and other commitments	115	44
Total loan and other commitments	28,914	27,754
Guarantees
Maximum Potential Undiscounted Future Payments	12,892		10,057	891	54	1,817	73
Liability Recorded	$ 168		$ 53	$ 11	$ 54	$ 48	$ 2
Additional Contingent Liabilities and Guarantees (Textual) [Abstract]
Guarantee Obligations								30.00%	70.00%	100.00%	0.00%	31.00%	71.00%
Return guarantee agreement with LIHTC investors
Compliance period of property					15 years
Expiration of Guarantees					Extend through 2018