Loans and Allowance for Loan Losses - Summary of Subsequent Default (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) loan	Mar. 31, 2021 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| loan	0	2
Recorded Investment \| $	$ 0	$ 478
Business Banking \| Commercial Portfolio Segment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| loan	0	1
Recorded Investment \| $	$ 0	$ 419
Consumer home equity \| Consumer Portfolio Segment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| loan	0	1
Recorded Investment \| $	$ 0	$ 59

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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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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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