Loans and the Allowance for Credit Losses - Summary of Amortized Cost Basis Loan Balances by Year of Origination and Credit Quality Indicator (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Recorded Investment [Line Items]
Total loans	$ 12,656,429	$ 11,638,461
30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	22,254	15,152
60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	24,970	9,729
90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	41,893	25,302
Home Equity [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	11,504	12,828
Amortized Cost Basis by Origination Year 2023	3,607	1,959
Amortized Cost Basis by Origination Year 2022	4,715	1,568
Amortized Cost Basis by Origination Year 2021	1,615	2,449
Amortized Cost Basis by Origination Year 2020	3,074	1,964
Amortized Cost Basis by Origination Year, Prior to 2019	26,351	26,482
Revolving Loans	768,526	685,163
Revolving Loans Converted to Term	1,718	1,806
Total loans	821,110	734,219
Home Equity [Member] | Current [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	11,504	12,675
Amortized Cost Basis by Origination Year 2023	1,857	1,235
Amortized Cost Basis by Origination Year 2022	2,220	1,467
Amortized Cost Basis by Origination Year 2021	969	1,571
Amortized Cost Basis by Origination Year 2020	2,623	1,614
Amortized Cost Basis by Origination Year, Prior to 2019	22,444	22,484
Revolving Loans	763,157	681,848
Revolving Loans Converted to Term	1,251	1,399
Total loans	806,025	724,293
Home Equity [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024		34
Amortized Cost Basis by Origination Year 2023	167	193
Amortized Cost Basis by Origination Year 2022	530	85
Amortized Cost Basis by Origination Year 2021	65	73
Amortized Cost Basis by Origination Year 2020	88	44
Amortized Cost Basis by Origination Year, Prior to 2019	1,226	947
Revolving Loans	5,166	3,315
Revolving Loans Converted to Term	178
Total loans	7,420	4,691
Home Equity [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024		119
Amortized Cost Basis by Origination Year 2023	656	318
Amortized Cost Basis by Origination Year 2022	1,170	16
Amortized Cost Basis by Origination Year 2021	346	68
Amortized Cost Basis by Origination Year 2020		76
Amortized Cost Basis by Origination Year, Prior to 2019	636	524
Revolving Loans	91
Revolving Loans Converted to Term	144	77
Total loans	3,043	1,198
Home Equity [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2023	927	213
Amortized Cost Basis by Origination Year 2022	795
Amortized Cost Basis by Origination Year 2021	235	737
Amortized Cost Basis by Origination Year 2020	363	230
Amortized Cost Basis by Origination Year, Prior to 2019	2,045	2,527
Revolving Loans	112
Revolving Loans Converted to Term	145	330
Total loans	4,622	4,037
Home Equity [Member] | Current-period gross charge-offs [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2023	355	139
Amortized Cost Basis by Origination Year 2022	132	57
Amortized Cost Basis by Origination Year 2021	65	29
Amortized Cost Basis by Origination Year 2020	35	79
Amortized Cost Basis by Origination Year, Prior to 2019	260	615
Revolving Loans	28	6
Revolving Loans Converted to Term	119
Total loans	994	925
Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,326,681	6,565,448
Commercial Real Estate [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,478	4,416
Commercial Real Estate [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,148	3,627
Commercial Real Estate [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	23,641	10,594
Residential Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	201,454	277,790
Amortized Cost Basis by Origination Year 2023	195,340	430,634
Amortized Cost Basis by Origination Year 2022	324,426	445,356
Amortized Cost Basis by Origination Year 2021	398,043	185,480
Amortized Cost Basis by Origination Year 2020	168,767	86,412
Amortized Cost Basis by Origination Year, Prior to 2019	480,564	464,727
Revolving Loans Converted to Term	751,492	548,175
Total loans	2,520,086	2,438,574
Residential Real Estate [Member] | Current [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	201,454	277,790
Amortized Cost Basis by Origination Year 2023	195,121	429,835
Amortized Cost Basis by Origination Year 2022	323,588	445,322
Amortized Cost Basis by Origination Year 2021	397,596	185,139
Amortized Cost Basis by Origination Year 2020	168,526	86,149
Amortized Cost Basis by Origination Year, Prior to 2019	471,081	456,818
Revolving Loans Converted to Term	749,593	548,147
Total loans	2,506,959	2,429,200
Residential Real Estate [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year, Prior to 2019	1,483	1,572
Total loans	1,483	1,572
Residential Real Estate [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2021	319	341
Amortized Cost Basis by Origination Year 2020	37
Amortized Cost Basis by Origination Year, Prior to 2019	2,763	2,130
Revolving Loans Converted to Term	404
Total loans	3,523	2,471
Residential Real Estate [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2023	219	799
Amortized Cost Basis by Origination Year 2022	838	34
Amortized Cost Basis by Origination Year 2021	128
Amortized Cost Basis by Origination Year 2020	204	263
Amortized Cost Basis by Origination Year, Prior to 2019	5,237	4,207
Revolving Loans Converted to Term	1,495	28
Total loans	8,121	5,331
Residential Real Estate [Member] | Current-period gross charge-offs [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2020		5
Amortized Cost Basis by Origination Year, Prior to 2019	250	387
Revolving Loans Converted to Term	58
Total loans	308	392
Consumer [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	52,438	85,480
Amortized Cost Basis by Origination Year 2023	57,608	60,006
Amortized Cost Basis by Origination Year 2022	38,399	22,853
Amortized Cost Basis by Origination Year 2021	12,623	13,707
Amortized Cost Basis by Origination Year 2020	5,930	11,134
Amortized Cost Basis by Origination Year, Prior to 2019	9,589	12,429
Revolving Loans	24,688	23,948
Revolving Loans Converted to Term		4
Total loans	201,275	229,561
Consumer [Member] | Current [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	51,073	84,526
Amortized Cost Basis by Origination Year 2023	55,821	57,661
Amortized Cost Basis by Origination Year 2022	36,994	21,592
Amortized Cost Basis by Origination Year 2021	11,744	13,189
Amortized Cost Basis by Origination Year 2020	5,640	10,958
Amortized Cost Basis by Origination Year, Prior to 2019	9,270	12,143
Revolving Loans	24,540	23,916
Revolving Loans Converted to Term		4
Total loans	195,082	223,989
Consumer [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	774	699
Amortized Cost Basis by Origination Year 2023	1,225	1,526
Amortized Cost Basis by Origination Year 2022	765	952
Amortized Cost Basis by Origination Year 2021	602	343
Amortized Cost Basis by Origination Year 2020	205	162
Amortized Cost Basis by Origination Year, Prior to 2019	197	119
Revolving Loans	148	32
Total loans	3,916	3,833
Consumer [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	271	191
Amortized Cost Basis by Origination Year 2023	327	616
Amortized Cost Basis by Origination Year 2022	517	195
Amortized Cost Basis by Origination Year 2021	161	112
Amortized Cost Basis by Origination Year 2020	51	5
Amortized Cost Basis by Origination Year, Prior to 2019	57	59
Total loans	1,384	1,178
Consumer [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	320	64
Amortized Cost Basis by Origination Year 2023	235	203
Amortized Cost Basis by Origination Year 2022	123	114
Amortized Cost Basis by Origination Year 2021	116	63
Amortized Cost Basis by Origination Year 2020	34	9
Amortized Cost Basis by Origination Year, Prior to 2019	65	108
Total loans	893	561
Consumer [Member] | Current-period gross charge-offs [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	382	251
Amortized Cost Basis by Origination Year 2023	1,578	1,921
Amortized Cost Basis by Origination Year 2022	1,466	901
Amortized Cost Basis by Origination Year 2021	497	301
Amortized Cost Basis by Origination Year 2020	166	100
Amortized Cost Basis by Origination Year, Prior to 2019	313	247
Revolving Loans		4
Total loans	4,402	3,725
Commercial Real Estate - Land and Construction [Member] | Current-period gross charge-offs [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2023	813
Revolving Loans Converted to Term		222
Total loans	813	222
Commercial Real Estate - Land and Construction [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	247,445	290,954
Amortized Cost Basis by Origination Year 2023	403,923	349,549
Amortized Cost Basis by Origination Year 2022	250,786	145,043
Amortized Cost Basis by Origination Year 2021	84,527	54,172
Amortized Cost Basis by Origination Year 2020	21,316	48,655
Amortized Cost Basis by Origination Year, Prior to 2019	52,499	35,942
Revolving Loans	145,408	82,587
Revolving Loans Converted to Term	146,179	48,963
Total loans	1,352,083	1,055,865
Commercial Real Estate - Land and Construction [Member] | Commercial Real Estate [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	832
Commercial Real Estate - Land and Construction [Member] | Commercial Real Estate [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	245,699	290,954
Amortized Cost Basis by Origination Year 2023	403,923	349,549
Amortized Cost Basis by Origination Year 2022	249,690	145,043
Amortized Cost Basis by Origination Year 2021	84,527	54,172
Amortized Cost Basis by Origination Year 2020	21,316	48,655
Amortized Cost Basis by Origination Year, Prior to 2019	52,485	35,917
Revolving Loans	145,032	82,288
Revolving Loans Converted to Term	144,702	46,781
Total loans	1,347,374	1,053,359
Commercial Real Estate - Land and Construction [Member] | Commercial Real Estate [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	1,746
Amortized Cost Basis by Origination Year 2022	1,096
Amortized Cost Basis by Origination Year, Prior to 2019	10	16
Revolving Loans	376	299
Revolving Loans Converted to Term	645	2,182
Total loans	3,873	2,497
Commercial Real Estate - Land and Construction [Member] | Commercial Real Estate [Member] | Classified - substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year, Prior to 2019	4	9
Revolving Loans Converted to Term	832
Total loans	836	9
Commercial Real Estate - Improved Property [Member] | Current-period gross charge-offs [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2022	75	372
Amortized Cost Basis by Origination Year 2021	7
Amortized Cost Basis by Origination Year, Prior to 2019	855	1,505
Total loans	937	1,877
Commercial Real Estate - Improved Property [Member] | Commercial Real Estate [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	562,444	496,063
Amortized Cost Basis by Origination Year 2023	502,786	1,093,322
Amortized Cost Basis by Origination Year 2022	1,067,326	612,401
Amortized Cost Basis by Origination Year 2021	557,988	588,343
Amortized Cost Basis by Origination Year 2020	529,601	543,180
Amortized Cost Basis by Origination Year, Prior to 2019	1,973,937	1,787,604
Revolving Loans	202,020	105,840
Revolving Loans Converted to Term	578,496	282,830
Total loans	5,974,598	5,509,583
Commercial Real Estate - Improved Property [Member] | Commercial Real Estate [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	7,646	4,416
Commercial Real Estate - Improved Property [Member] | Commercial Real Estate [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,148	3,627
Commercial Real Estate - Improved Property [Member] | Commercial Real Estate [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	23,641	10,594
Commercial Real Estate - Improved Property [Member] | Commercial Real Estate [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	542,333	494,142
Amortized Cost Basis by Origination Year 2023	472,746	1,076,535
Amortized Cost Basis by Origination Year 2022	1,038,745	603,354
Amortized Cost Basis by Origination Year 2021	543,212	581,540
Amortized Cost Basis by Origination Year 2020	512,916	514,523
Amortized Cost Basis by Origination Year, Prior to 2019	1,897,950	1,706,804
Revolving Loans	200,572	103,467
Revolving Loans Converted to Term	482,132	257,029
Total loans	5,690,606	5,337,394
Commercial Real Estate - Improved Property [Member] | Commercial Real Estate [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	365
Amortized Cost Basis by Origination Year 2023	28,204	16,270
Amortized Cost Basis by Origination Year 2022	5,188	8,630
Amortized Cost Basis by Origination Year 2021	13,590	4,387
Amortized Cost Basis by Origination Year 2020	6,733	5,185
Amortized Cost Basis by Origination Year, Prior to 2019	39,845	44,861
Revolving Loans	825	2,373
Revolving Loans Converted to Term	94,572	25,767
Total loans	189,322	107,473
Commercial Real Estate - Improved Property [Member] | Commercial Real Estate [Member] | Classified - substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	19,746	1,921
Amortized Cost Basis by Origination Year 2023	1,836	517
Amortized Cost Basis by Origination Year 2022	23,393	417
Amortized Cost Basis by Origination Year 2021	1,186	2,416
Amortized Cost Basis by Origination Year 2020	9,952	23,472
Amortized Cost Basis by Origination Year, Prior to 2019	36,142	35,939
Revolving Loans	623
Revolving Loans Converted to Term	1,792	34
Total loans	94,670	64,716
Commercial and Industrial [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	227,055	239,554
Amortized Cost Basis by Origination Year 2023	147,177	235,503
Amortized Cost Basis by Origination Year 2022	210,747	140,482
Amortized Cost Basis by Origination Year 2021	108,592	80,591
Amortized Cost Basis by Origination Year 2020	49,947	47,418
Amortized Cost Basis by Origination Year, Prior to 2019	260,737	286,268
Revolving Loans	639,755	567,823
Revolving Loans Converted to Term	143,267	73,020
Total loans	1,787,277	1,670,659
Commercial and Industrial [Member] | 30-59 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	957	640
Commercial and Industrial [Member] | 60-89 Days Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	8,872	1,255
Commercial and Industrial [Member] | 90 Days or More Past Due [Member]
Financing Receivable, Recorded Investment [Line Items]
Total loans	4,616	4,779
Commercial and Industrial [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	225,344	238,427
Amortized Cost Basis by Origination Year 2023	139,460	234,520
Amortized Cost Basis by Origination Year 2022	206,252	136,998
Amortized Cost Basis by Origination Year 2021	106,446	78,836
Amortized Cost Basis by Origination Year 2020	48,285	39,259
Amortized Cost Basis by Origination Year, Prior to 2019	250,438	252,826
Revolving Loans	616,831	541,400
Revolving Loans Converted to Term	128,253	64,417
Total loans	1,721,309	1,586,683
Commercial and Industrial [Member] | Criticized [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	217	1,094
Amortized Cost Basis by Origination Year 2023	7,335	834
Amortized Cost Basis by Origination Year 2022	3,337	3,169
Amortized Cost Basis by Origination Year 2021	921	1,490
Amortized Cost Basis by Origination Year 2020	1,597	7,334
Amortized Cost Basis by Origination Year, Prior to 2019	7,660	31,526
Revolving Loans	20,464	20,626
Revolving Loans Converted to Term	7,274	7,131
Total loans	48,805	73,204
Commercial and Industrial [Member] | Classified - substandard [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	1,494	33
Amortized Cost Basis by Origination Year 2023	382	149
Amortized Cost Basis by Origination Year 2022	1,158	315
Amortized Cost Basis by Origination Year 2021	1,225	265
Amortized Cost Basis by Origination Year 2020	65	825
Amortized Cost Basis by Origination Year, Prior to 2019	2,639	1,916
Revolving Loans	2,460	5,797
Revolving Loans Converted to Term	7,740	1,472
Total loans	17,163	10,772
Commercial and Industrial [Member] | Current-period gross charge-offs [Member]
Financing Receivable, Recorded Investment [Line Items]
Amortized Cost Basis by Origination Year 2024	48	98
Amortized Cost Basis by Origination Year 2023	648	205
Amortized Cost Basis by Origination Year 2022	1,048	603
Amortized Cost Basis by Origination Year 2021	228	353
Amortized Cost Basis by Origination Year 2020	162	20
Amortized Cost Basis by Origination Year, Prior to 2019	1,029	463
Revolving Loans	1
Revolving Loans Converted to Term	7,369	541
Total loans	$ 10,533	$ 2,283