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Asset Quality - Schedule of Performance of Loans That Have Been Modified in the Last 12 Months (Details) $ in Millions | Dec. 31, 2023 USD ($)
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Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | $ 295
Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 267
30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 27
90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 1
Total commercial loans |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 269
Total commercial loans | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 244
Total commercial loans | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 25
Total commercial loans | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Commercial and Industrial |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 263
Total commercial loans | Commercial and Industrial | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 238
Total commercial loans | Commercial and Industrial | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 25
Total commercial loans | Commercial and Industrial | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Commercial mortgage |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 6
Total commercial loans | Commercial mortgage | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 6
Total commercial loans | Commercial mortgage | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Commercial mortgage | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Construction |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Construction | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Construction | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Construction | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Total commercial real estate loans |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 269
Total commercial loans | Total commercial real estate loans | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 244
Total commercial loans | Total commercial real estate loans | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 25
Total commercial loans | Total commercial real estate loans | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Commercial lease financing |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Commercial lease financing | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Commercial lease financing | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total commercial loans | Commercial lease financing | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 26
Total consumer loans | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 23
Total consumer loans | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 2
Total consumer loans | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 1
Total consumer loans | Real estate — residential mortgage |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 10
Total consumer loans | Real estate — residential mortgage | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 9
Total consumer loans | Real estate — residential mortgage | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 1
Total consumer loans | Real estate — residential mortgage | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans | Home equity loans |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 9
Total consumer loans | Home equity loans | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 8
Total consumer loans | Home equity loans | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans | Home equity loans | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 1
Total consumer loans | Consumer direct loans |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 3
Total consumer loans | Consumer direct loans | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 3
Total consumer loans | Consumer direct loans | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans | Consumer direct loans | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans | Credit cards |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 4
Total consumer loans | Credit cards | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 3
Total consumer loans | Credit cards | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 1
Total consumer loans | Credit cards | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans | Consumer indirect loans |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans | Consumer indirect loans | Current |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans | Consumer indirect loans | 30-89 Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | 0
Total consumer loans | Consumer indirect loans | 90 and Greater Days Past Due |
Financing Receivable, Past Due [Line Items] |
Total loans modified in last 12 months | $ 0

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