Loans - Consumer, Excluding Credit Card Loan Portfolio, Loan Modifications, New TDRs (Details) - Consumer, excluding credit card - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Total residential real estate – excluding PCI
Financing Receivable, Impaired [Line Items]
New TDRs	$ 122	$ 139	$ 555	$ 457
Residential mortgage
Financing Receivable, Impaired [Line Items]
New TDRs	67	57	314	225
Home equity
Financing Receivable, Impaired [Line Items]
New TDRs	$ 55	$ 82	$ 241	$ 232

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Balance Type:	debit
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