Commitments and Guarantees (Other Commitments) (Details) - USD ($)	Dec. 31, 2015	Dec. 31, 2014
Other Commitments [Line Items]
Commitments	$ 155,141,000,000	$ 154,937,000,000
Commitments to extend credit [Member]
Other Commitments [Line Items]
Commitments	142,489,000,000	138,592,000,000
Commitments to extend credit [Member] | Total commercial lending [Member]
Other Commitments [Line Items]
Commitments	101,252,000,000	98,742,000,000
Commitments to extend credit [Member] | Home Equity Lines of Credit [Member]
Other Commitments [Line Items]
Commitments	17,268,000,000	17,839,000,000
Commitments to extend credit [Member] | Credit Card [Member]
Other Commitments [Line Items]
Commitments	19,937,000,000	17,833,000,000
Commitments to extend credit [Member] | Other [Member]
Other Commitments [Line Items]
Commitments	4,032,000,000	4,178,000,000
Standby letters of credit [Member]
Other Commitments [Line Items]
Commitments	8,765,000,000	9,991,000,000
Standby letters of credit [Member] | Remarketing Programs [Member]
Other Commitments [Line Items]
Commitments	4,700,000,000	5,200,000,000
Reinsurance Agreements [Member]
Other Commitments [Line Items]
Commitments	2,010,000,000	4,297,000,000
Reinsurance Agreements [Member] | Accidental Death and Dismemberment [Member]
Other Commitments [Line Items]
Maximum Exposure	1,600,000,000	1,800,000,000
Reinsurance Agreements [Member] | Credit Life Accident and Health [Member]
Other Commitments [Line Items]
Maximum Exposure	400,000,000	500,000,000
Reinsurance Agreements [Member] | Lender Placed Hazard [Member]
Other Commitments [Line Items]
Maximum Exposure		2,000,000,000
Standby bond purchase agreements [Member]
Other Commitments [Line Items]
Commitments	911,000,000	1,095,000,000
Other commitments [Member]
Other Commitments [Line Items]
Commitments	966,000,000	962,000,000
Other commitments [Member] | Investments in qualified affordable housing projects [Member]
Other Commitments [Line Items]
Commitments	$ 500,000,000	$ 400,000,000