Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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- Definition

The increase (decrease) during the reporting period in the value of loans or securitized loans that are held with the intention to sell in the near future.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3461-108585

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- Definition

Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL49126937-111524

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- References

No definition available.

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

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Loans and ACL - Narrative (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
Loans and ACL - Narrative (Details) - USD ($) $ in Millions	Sep. 30, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Receivables [Abstract]
Modifications that defaulted during the period that had been classified as a TDR during the previous 12 months		$ 21	$ 13	$ 39	$ 36
Residential mortgage loans in process of foreclosure		$ 240		240		$ 253
Subsequent Event [Line Items]
Loans expected to be sold				$ 326	$ 516
Residential mortgage \| Subsequent Event
Subsequent Event [Line Items]
Loans expected to be sold	$ 4,000