Intangible Assets (Schedule of Other Intangible Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	$ 1,268	$ 1,222
Finite-Lived Intangible Assets, Accumulated Amortization	1,164	1,135
Finite-Lived Intangible Assets, Net	122	105
Core Deposits [Member]
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	1,011	1,011
Finite-Lived Intangible Assets, Accumulated Amortization	991	980
Finite-Lived Intangible Assets, Net	20	31
Purchased Credit Card Relationships [Member]
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	175	175
Finite-Lived Intangible Assets, Accumulated Amortization	149	140
Finite-Lived Intangible Assets, Net	26	35
Other Intangible Assets [Member]
Other Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Gross	82	36
Finite-Lived Intangible Assets, Accumulated Amortization	24	15
Finite-Lived Intangible Assets, Net	58	21
Fannie Mae DUS License [Member]
Other Intangible Assets [Line Items]
Other Intangible Assets, Net	15	15
Other Intangible Assets [Member]
Other Intangible Assets [Line Items]
Other Intangible Assets, Net	$ 3	$ 3

Other Intangible Assets [Line Items]

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
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