Loans and Leases - Loan Modification Activities that were Considered Troubled Debt Restructurings (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) Modification	Dec. 31, 2020 USD ($) Modification	Dec. 31, 2019 USD ($) Modification
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	2,320	5,250	412
Pre-modification Recorded Investment	$ 533,752	$ 862,507	$ 143,556
Loans and leases, net of unearned discount	$ 529,323	$ 806,046	$ 127,024
Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	284	394	150
Pre-modification Recorded Investment	$ 185,458	$ 246,479	$ 63,715
Loans and leases, net of unearned discount	$ 182,880	$ 199,918	$ 63,356
Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	99	161	51
Pre-modification Recorded Investment	$ 202,878	$ 310,578	$ 48,315
Loans and leases, net of unearned discount	$ 200,837	$ 295,231	$ 31,345
Other Commercial Construction [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	3	2	3
Pre-modification Recorded Investment	$ 542	$ 13,602	$ 1,559
Loans and leases, net of unearned discount	$ 532	$ 13,573	$ 1,500
Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	373	631	83
Pre-modification Recorded Investment	$ 108,325	$ 202,985	$ 21,695
Loans and leases, net of unearned discount	$ 108,635	$ 207,517	$ 22,726
Residential Limited Documentation [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	21	30	6
Pre-modification Recorded Investment	$ 2,920	$ 7,413	$ 1,409
Loans and leases, net of unearned discount	$ 2,865	$ 8,332	$ 1,443
Home Equity Lines and Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	89	259	41
Pre-modification Recorded Investment	$ 6,430	$ 17,228	$ 4,127
Loans and leases, net of unearned discount	$ 6,375	$ 17,254	$ 4,180
Recreational Finance [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	281	428	10
Pre-modification Recorded Investment	$ 9,931	$ 16,392	$ 265
Loans and leases, net of unearned discount	$ 9,931	$ 16,392	$ 265
Automobile [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	807	2,249	66
Pre-modification Recorded Investment	$ 14,668	$ 39,951	$ 1,141
Loans and leases, net of unearned discount	$ 14,668	$ 39,951	$ 1,141
Other [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	362	1,095
Pre-modification Recorded Investment	$ 2,597	$ 7,788
Loans and leases, net of unearned discount	$ 2,597	$ 7,788
Residential Builder and Developer [Member]
Financing Receivable, Modifications [Line Items]
Number of modifications | Modification	1	1	2
Pre-modification Recorded Investment	$ 3	$ 91	$ 1,330
Loans and leases, net of unearned discount	3	90	1,068
Principal Deferral [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	246,598	545,415	29,481
Principal Deferral [Member] | Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	46,806	70,671	10,485
Principal Deferral [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	67,387	204,591	5,193
Principal Deferral [Member] | Other Commercial Construction [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	532	13,573
Principal Deferral [Member] | Residential [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	95,769	183,878	10,819
Principal Deferral [Member] | Residential Limited Documentation [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	2,865	7,100	399
Principal Deferral [Member] | Home Equity Lines and Loans [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	6,054	5,882	176
Principal Deferral [Member] | Recreational Finance [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	9,931	16,388	265
Principal Deferral [Member] | Automobile [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	14,654	39,949	1,076
Principal Deferral [Member] | Other [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	2,597	3,383
Principal Deferral [Member] | Residential Builder and Developer [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	3		1,068
Interest Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount		803
Interest Rate Reduction [Member] | Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount		298
Interest Rate Reduction [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount		505
Other [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	71,760	36,479
Other [Member] | Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	40,558	31,605
Other [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	31,202	4,874
Combination of Concession Types [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	210,965	223,349	97,543
Combination of Concession Types [Member] | Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	95,516	97,344	52,871
Combination of Concession Types [Member] | Commercial Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	102,248	85,261	26,152
Combination of Concession Types [Member] | Other Commercial Construction [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount			1,500
Combination of Concession Types [Member] | Residential [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	12,866	23,639	11,907
Combination of Concession Types [Member] | Residential Limited Documentation [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount		1,232	1,044
Combination of Concession Types [Member] | Home Equity Lines and Loans [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	321	11,372	4,004
Combination of Concession Types [Member] | Recreational Finance [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount		4
Combination of Concession Types [Member] | Automobile [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount	$ 14	2	$ 65
Combination of Concession Types [Member] | Other [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount		4,405
Combination of Concession Types [Member] | Residential Builder and Developer [Member]
Financing Receivable, Modifications [Line Items]
Loans and leases, net of unearned discount		$ 90