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	3 Months Ended
Mar. 31, 2023 USD ($)
Financing Receivable, Modifications
Year One	$ 0
Year Two	1
Year Three	11
Year Four	0
Year Five	0
Prior	0
Revolving Loans	21
Revolving Loans Converted to Term Loans	0
Total	33
Commercial and industrial loans
Financing Receivable, Modifications
Year One	0
Year Two	1
Year Three	11
Year Four	0
Year Five	0
Prior	0
Revolving Loans	20
Revolving Loans Converted to Term Loans	0
Total	32
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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