Commitments, Contingencies and Guarantees (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($)
Commitments to extend credit
Commitment, Contingencies and Guarantees disclosures
Commitments	$ (35,514)
Issued standby and commercial letters of credit
Commitment, Contingencies and Guarantees disclosures
Commitments	$ (5,686)
Maximum term	1 year
Carrying value	$ 4
Other commitments
Commitment, Contingencies and Guarantees disclosures
Commitments	(115)
Oil and gas | Commitments to extend credit
Commitment, Contingencies and Guarantees disclosures
Commitments	$ (7,351)