Allowance for Loan and Lease Losses, Reversal or Charge-off of Allowances for Credit Losses

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- Definition

Measurement of ECL Measurements [Line Items]

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- Definition

Number Of Forward-looking Economic Scenarios

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Number Of Updated Forward-looking Economic Scenarios

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- Definition

Amount of writeoff of accrued interest on financing receivable recognized by reversing interest income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 3D
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL120267969-210447

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- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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- Definition

Amount of expense reversal of allowance for credit loss on financing receivable transferred to held-for-sale classification.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
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-URI http://asc.fasb.org/extlink&oid=124265262&loc=SL120268815-111004

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Allowance for Credit Losses - Narrative (Details) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2021 USD ($) scenario	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($) scenario	Dec. 31, 2020 USD ($)
Measurement of ECL Measurements [Line Items]
Number of forward-looking economic scenarios \| scenario	3			3
Number of updated forward-looking economic scenarios \| scenario	4			4
Reduction to the provision for credit losses	$ 22
Increase in allowance for credit losses	$ 14
Exit of Mass Market Retail Banking Business and Remaining Retail Credit Card Portfolio
Measurement of ECL Measurements [Line Items]
Reduction to the provision for credit losses			$ 101
Reversal or charge-off of allowances for credit losses			157
Commercial loans: \| Exit of Mass Market Retail Banking Business and Remaining Retail Credit Card Portfolio
Measurement of ECL Measurements [Line Items]
Reduction to the provision for credit losses			$ 0
Commercial loans: \| Real Estate, including Construction
Measurement of ECL Measurements [Line Items]
Reduction to the provision for credit losses		$ 24
Commercial loans held for sale
Measurement of ECL Measurements [Line Items]
Charge-off of accrued interest receivables				$ 5	$ 7