Loans - Consumer, Excluding Credit Card Loans, Loan Modifications, New TDRs (Details) - Consumer, excluding credit card - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Total residential real estate – excluding PCI
Financing Receivable, Impaired [Line Items]
New TDRs	$ 639	$ 668	$ 732
Home equity
Financing Receivable, Impaired [Line Items]
New TDRs	385	401	321
Residential mortgage
Financing Receivable, Impaired [Line Items]
New TDRs	$ 254	$ 267	$ 411

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration