Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

+ Details

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

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Loans and Allowance for Loan Losses - Average Investment in Impaired Loans and Interest Income Recognized for Impaired Loans (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Loan impairment
Average Recorded Investment	$ 760	$ 752	$ 766	$ 765
Recognized Interest Income	17	4	36	10
Commercial
Loan impairment
Average Recorded Investment	458	491	458	501
Recognized Interest Income	13	1	27	5
Consumer
Loan impairment
Average Recorded Investment	302	261	308	264
Recognized Interest Income	4	3	9	5
Commercial and industrial \| Commercial
Loan impairment
Average Recorded Investment	296	419
Recognized Interest Income	3	0
ERROR in label resolution. \| Commercial
Loan impairment
Average Recorded Investment	51	61
Recognized Interest Income	8	1
Residential mortgage \| Consumer
Loan impairment
Average Recorded Investment	264	233
Recognized Interest Income	3	2
Construction \| Commercial
Loan impairment
Average Recorded Investment	111	11
Recognized Interest Income	2	0
Home equity and other consumer loans \| Consumer
Loan impairment
Average Recorded Investment	38	28
Recognized Interest Income	$ 1	$ 1
Commercial and industrial \| Commercial Loans Portfolio Segment [Member]
Loan impairment
Average Recorded Investment			294	447
Recognized Interest Income			5	4
Construction \| Commercial Loans Portfolio Segment [Member]
Loan impairment
Average Recorded Investment			120	14
Recognized Interest Income			4	0
Home equity and other consumer loans \| Consumer Loans
Loan impairment
Average Recorded Investment			40	29
Recognized Interest Income			2	1
Residential mortgage \| Consumer Loans
Loan impairment
Average Recorded Investment			268	235
Recognized Interest Income			7	4
Commercial mortgage \| Commercial Loans Portfolio Segment [Member]
Loan impairment
Average Recorded Investment			44	40
Recognized Interest Income			$ 18	$ 1