Credit Quality and the Allowance for Loan and Lease Losses - Summary of Gross Charge-Offs Within the Commercial Portfolio Segments, by Class and Vintage (Details) - Commercial $ in Millions	6 Months Ended
Jun. 30, 2023 USD ($)
Financing Receivable, Modifications
Year One	$ 0
Year Two	5
Year Three	11
Year Four	1
Year Five	0
Prior	5
Revolving Loans	47
Revolving Loans Converted to Term Loans	0
Total	69
Commercial and industrial loans
Financing Receivable, Modifications
Year One	0
Year Two	5
Year Three	11
Year Four	1
Year Five	0
Prior	5
Revolving Loans	45
Revolving Loans Converted to Term Loans	0
Total	67
Commercial mortgage owner-occupied loans
Financing Receivable, Modifications
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior	0
Revolving Loans	1
Revolving Loans Converted to Term Loans	0
Total	1
Commercial construction loans
Financing Receivable, Modifications
Year One	0
Year Two	0
Year Three	0
Year Four	0
Year Five	0
Prior	0
Revolving Loans	1
Revolving Loans Converted to Term Loans	0
Total	$ 1

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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