Goodwill and Intangible Assets - Additional Information (Details) (USD $)	12 Months Ended														12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012 Retail Banking [Member]	Dec. 31, 2012 Wealth and Investment Management [Member]	Dec. 31, 2012 Diversified Commercial Banking [Member]	Dec. 31, 2012 Consumer Banking and Private Wealth Management [Member] Retail Banking [Member]	Dec. 31, 2012 Consumer Banking and Private Wealth Management [Member] Wealth and Investment Management [Member]	Dec. 31, 2012 Wholesale Banking [Member] Retail Banking [Member]	Dec. 31, 2012 Wholesale Banking [Member] Wealth and Investment Management [Member]	Dec. 31, 2012 Wholesale Banking [Member] Diversified Commercial Banking [Member]	Sep. 30, 2012 RidgeWorth Capital Management [Member]	Sep. 30, 2012 Wholesale Banking [Member]	Sep. 30, 2012 Consumer Banking and Private Wealth Management [Member]	Dec. 31, 2012 GenSpring Family Offices, LLC [Member]	Dec. 31, 2012 Mortgage Servicing Rights [Member]	Dec. 31, 2011 Mortgage Servicing Rights [Member]	Dec. 31, 2010 Mortgage Servicing Rights [Member]
Goodwill [Line Items]
Servicing Fees, Net	$ 260,000,000	$ 224,000,000	$ 358,000,000													$ 333,000,000	$ 364,000,000	$ 399,000,000
Goodwill, Intersegment Transfers	0			(4,854,000,000)	(382,000,000)	(928,000,000)	3,600,000,000	335,000,000	1,300,000,000	47,000,000	928,000,000
Percentage of Fair Value in Excess of Carrying Value												147.00%	31.00%	21.00%
Goodwill, Impairment Loss	7,000,000	0	0	0	0	0									7,000,000
Assets that Continue to be Recognized, Securitized or Asset-backed Financing Arrangement Assets and any Other Financial Assets Managed Together, Principal Amount Outstanding																144,900,000,000	157,800,000,000
Principal Amount Outstanding of Loans Serviced For Third Parties																113,200,000,000	124,100,000,000
Loan Principal Amount Outstanding Underlying Mortgage Servicing Rights Sold																$ 2,100,000,000
change in amount of loans serviced for third parties	(9.00%)