Loans and Allowance for Credit Losses, Significant Activity (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Loans and Allowance for Credit Losses, Significant Activity [Abstract]
Purchases	$ 332	$ 256
Sales	(600)	(460)
Transfers to MLHFS/LHFS	(3)	(1,973)
Commercial Portfolio Segment [Member]
Loans and Allowance for Credit Losses, Significant Activity [Abstract]
Purchases	329	256
Sales	(421)	(460)
Transfers to MLHFS/LHFS	(3)	(420)
Total Consumer [Member]
Loans and Allowance for Credit Losses, Significant Activity [Abstract]
Purchases	3	0
Sales	(179)	0
Transfers to MLHFS/LHFS	$ 0	$ (1,553)

No definition available.

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- Definition

The amount of financing receivables reclassified to held for sale during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The amount of any significant purchases of financing receivables during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

+ Details

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- Definition

The amount of any significant sales of financing receivables during the reporting period.

+ References

+ Details

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- Details

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- Details

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