Loans and Leases - Summary of Originated Troubled Debt Restructurings by Class of Loans and Leases, Payment Default (Detail) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) contract	Dec. 31, 2020 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	3	30
Recorded Investment \| $	$ 0	$ 3
Total commercial loans and leases
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	10
Recorded Investment \| $	$ 0	$ 3
Total commercial loans and leases \| Commercial real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	8
Recorded Investment \| $	$ 0	$ 3
Total commercial loans and leases \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	2
Recorded Investment \| $	$ 0	$ 0
Total consumer loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	2	20
Recorded Investment \| $	$ 0	$ 0
Total consumer loans \| Direct installment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	12
Recorded Investment \| $	$ 0	$ 0
Total consumer loans \| Residential mortgages
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	4
Recorded Investment \| $	$ 0	$ 0
Total consumer loans \| Consumer lines of credit
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	4
Recorded Investment \| $	$ 0	$ 0

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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- Definition

Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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