Goodwill and Other Intangible Assets - Changes in Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Beginning Balance	$ 2,516	$ 2,538
KIBS divestiture		(22)
Reallocation of goodwill	0
Laurel Road acquisition	148
Ending Balance	2,664	2,516
Consumer Bank [Member]
Goodwill [Roll Forward]
Beginning Balance	2,102	2,124
KIBS divestiture		(22)
Reallocation of goodwill	(498)
Laurel Road acquisition	148
Ending Balance	1,752	2,102
Commercial Bank [Member]
Goodwill [Roll Forward]
Beginning Balance	414	414
KIBS divestiture		0
Reallocation of goodwill	498
Laurel Road acquisition	0
Ending Balance	$ 912	$ 414

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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