Loans and Leases - Schedule Of Troubled Debt Restructurings Occurring During The Year (Details) $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan		367
Pre-Modification Outstanding Recorded Investment		$ 91
Post-Modification Outstanding Recorded Investment	$ 25	$ 85
Consumer: \| Credit card and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan		81
Pre-Modification Outstanding Recorded Investment		$ 12
Post-Modification Outstanding Recorded Investment		$ 12
C&I \| Commercial: \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan		6
Pre-Modification Outstanding Recorded Investment		$ 30
Post-Modification Outstanding Recorded Investment		$ 24
CRE \| Commercial: \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan		1
Pre-Modification Outstanding Recorded Investment		$ 1
Post-Modification Outstanding Recorded Investment		$ 1
HELOC \| Consumer: \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan		98
Pre-Modification Outstanding Recorded Investment		$ 7
Post-Modification Outstanding Recorded Investment		$ 7
Real estate installment loans \| Consumer: \| Consumer Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number \| loan		181
Pre-Modification Outstanding Recorded Investment		$ 41
Post-Modification Outstanding Recorded Investment		$ 41

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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