Allowance for Credit Losses (Summary of Loans Restructured and Subsequently Defaulted Under the Restructured Terms) (Detail) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2022 USD ($) contract	Jun. 30, 2021 USD ($) contract	Jun. 30, 2022 USD ($) contract	Jun. 30, 2021 USD ($) contract	Jun. 30, 2022 USD ($) contract	Jun. 30, 2021 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count | contract	16	16	29	36	57	93
TDRs, balance | $	$ 2,421	$ 4,199	$ 5,518	$ 6,325	$ 13,061	$ 19,383
Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count | contract	12	11	13	12
TDRs, balance | $	$ 4,814	$ 2,926	$ 5,056	$ 3,133
Commercial, industrial and other | Commercial, industrial and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count | contract	2	3	5	5	16	14
TDRs, balance | $	$ 186	$ 395	$ 468	$ 546	$ 4,995	$ 3,875
Commercial, industrial and other | Commercial, industrial and other | Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count | contract	10	4	11	4
TDRs, balance | $	$ 4,469	$ 1,371	$ 4,711	$ 1,371
Commercial real estate | Non-construction
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count | contract	0	3	2	5	2	9
TDRs, balance | $	$ 0	$ 2,707	$ 1,907	$ 2,944	$ 1,907	$ 4,090
Commercial real estate | Non-construction | Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count | contract	0	2	0	3
TDRs, balance | $	$ 0	$ 1,176	$ 0	$ 1,383
Residential real estate and other
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count | contract	14	10	22	26	39	70
TDRs, balance | $	$ 2,235	$ 1,097	$ 3,143	$ 2,835	$ 6,159	$ 11,418
Residential real estate and other | Payment Deferral
Financing Receivable, Troubled Debt Restructuring [Line Items]
TDRs, count | contract	2	5	2	5
TDRs, balance | $	$ 345	$ 379	$ 345	$ 379