Loans and Leases and the Allowance for Credit Losses - Loan and Leases Considered Nonaccrual and Interest Income Recognized on Loans (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Jan. 01, 2022
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	$ 986,279	$ 827,842
Amortized Cost without Allowance	1,570,520	1,306,389
Total	2,556,799	2,134,231
Amortized Cost	2,438,435		$ 2,060,083
Interest Income Recognized	16,863	29,616
Commercial, Financial, Leasing, etc. [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	185,867	171,322
Amortized Cost without Allowance	196,401	103,824
Total	382,268	275,146
Amortized Cost	347,204		221,022
Interest Income Recognized	2,279	13,594
Commercial [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	404,564	222,771
Amortized Cost without Allowance	1,112,091	934,915
Total	1,516,655	1,157,686
Amortized Cost	1,396,662		1,069,280
Interest Income Recognized	5,501	6,131
Residential Builder and Developer [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	3,303	524
Amortized Cost without Allowance		2,392
Total	3,303	2,916
Amortized Cost	1,229		3,005
Interest Income Recognized	366	1,428
Other Commercial Construction [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	94,188	29,914
Amortized Cost without Allowance	48,827	20,941
Total	143,015	50,855
Amortized Cost	124,937		111,405
Interest Income Recognized	1,662	626
Residential [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	124,574	191,495
Amortized Cost without Allowance	129,072	150,176
Total	253,646	341,671
Amortized Cost	272,090		355,858
Interest Income Recognized	4,376	6,541
Residential Limited Documentation [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	40,165	80,590
Amortized Cost without Allowance	28,770	42,922
Total	68,935	123,512
Amortized Cost	77,814		122,888
Interest Income Recognized	164	196
Home Equity Lines and Loans [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	39,131	32,783
Amortized Cost without Allowance	41,635	38,706
Total	80,766	71,489
Amortized Cost	84,788		70,488
Interest Income Recognized	2,221	809
Recreational Finance [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	24,409	24,350
Amortized Cost without Allowance	9,777	7,196
Total	34,186	31,546
Amortized Cost	44,630		27,811
Interest Income Recognized	171	161
Automobile [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	22,926	30,129
Amortized Cost without Allowance	3,916	5,221
Total	26,842	35,350
Amortized Cost	39,584		34,037
Interest Income Recognized	35	38
Other [Member]
Financing Receivable, Impaired [Line Items]
Amortized Cost with Allowance	47,152	43,964
Amortized Cost without Allowance	31	96
Total	47,183	44,060
Amortized Cost	49,497		$ 44,289
Interest Income Recognized	$ 88	$ 92