Loans - Consumer, Excluding Credit Card Loan Portfolio, Loan Modifications, New TDRs (Details) - Consumer, excluding credit card - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Financing Receivable, Impaired [Line Items]
New TDRs	$ 189	$ 154
Home equity
Financing Receivable, Impaired [Line Items]
New TDRs	126	72
Residential Mortgage
Financing Receivable, Impaired [Line Items]
New TDRs	$ 63	$ 82