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Credit Quality And Allowance For Credit Losses (Nonaccrual Loans) (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  | $ 60 | $ 127
Nonaccrual loans with related allowance |  | 204 | 220
Nonaccrual loans |  | 264 | 347
Business loans | Commercial borrower |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  | 12 | 63
Nonaccrual loans with related allowance |  | 204 | 220
Nonaccrual loans |  | 216 | 283
Business loans | Commercial borrower | Domestic loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  | 8 | 57
Nonaccrual loans with related allowance |  | 165 | 195
Nonaccrual loans |  | 173 | 252
Business loans | Commercial borrower | Non-US |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  | 0 |
Nonaccrual loans with related allowance |  | 5 |
Nonaccrual loans |  | 5 |
Retail loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  | 48 | 64
Nonaccrual loans with related allowance |  | 0 | 0
Nonaccrual loans |  | 48 | 64
Retail loans | Home equity |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans |  | 12 | 17
Real estate construction | Business loans | Commercial borrower | Domestic loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans |  | 6 | 1
Real estate construction | Commercial Real Estate business line | Business loans | Commercial borrower | Domestic loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans | [1] | 0 | 0
Real estate construction | Other business lines | Business loans | Commercial borrower | Domestic loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance | [2] | 0 | 0
Nonaccrual loans with related allowance | [2] | 6 | 1
Nonaccrual loans | [2] | 6 | 1
Commercial mortgage | Business loans | Commercial borrower | Domestic loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  | 4 | 6
Nonaccrual loans with related allowance |  | 28 | 23
Nonaccrual loans |  | 32 | 29
Commercial mortgage | Commercial Real Estate business line | Business loans | Commercial borrower | Domestic loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance | [1] | 0 | 1
Nonaccrual loans with related allowance | [1] | 1 | 2
Nonaccrual loans | [1] | 1 | 3
Commercial mortgage | Other business lines | Business loans | Commercial borrower | Domestic loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance | [2] | 4 | 5
Nonaccrual loans with related allowance | [2] | 27 | 21
Nonaccrual loans | [2] | 31 | 26
Residential mortgage | Retail loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  | 36 | 47
Nonaccrual loans with related allowance |  | 0 | 0
Nonaccrual loans |  | 36 | 47
Home equity | Retail loans | Home equity |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  | 12 | 17
Nonaccrual loans with related allowance |  | 0 | 0
Nonaccrual loans |  | 12 | 17
Other consumer | Retail loans | Home equity |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans |  | $ 0 | 0
Business Loans | Lease financing | Commercial borrower | Domestic loans |  |  |
Financing Receivable, Impaired [Line Items] |  |  |
Nonaccrual loans with no related allowance |  |  | 0
Nonaccrual loans with related allowance |  |  | 1
Nonaccrual loans |  |  | $ 1
[1] | Primarily loans to real estate developers.
[2] | Primarily loans secured by owner-occupied real estate.

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