Loans and Allowance for Credit Losses - Loan Balances by Year of Origination and Internally Assigned Risk Rating (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Total Loan Balance
Current fiscal year	$ 1,166,736	$ 893,015
Year two	890,701	1,134,650
Year three	995,373	1,191,528
Year four	988,809	897,782
Year five	722,161	421,743
More than five years	1,900,975	1,885,462
Revolving	1,362,700	1,284,808
Revolving-Term	44,502	33,970
Total	8,071,957	7,742,958
Year-to-date Gross Charge-offs
Current fiscal year	1,288	839
Year two	89	191
Year three	4,316	288
Year four	5,311	1,338
Year five	255	91
More than five years	5,434	6,837
Revolving	224	1,118
Revolving-Term	1,158	1,486
Total	18,075	12,188
Pass
Total Loan Balance
Current fiscal year	1,166,736	892,431
Year two	885,598	1,128,069
Year three	979,038	1,171,403
Year four	975,693	870,715
Year five	685,519	417,507
More than five years	1,821,062	1,775,175
Revolving	1,322,643	1,243,868
Revolving-Term	39,961	30,962
Total	7,876,250	7,530,130
Special mention
Total Loan Balance
Current fiscal year	0	0
Year two	3,651	2,020
Year three	2,423	17,638
Year four	8,686	2,112
Year five	3,288	157
More than five years	42,371	65,401
Revolving	8,437	11,322
Revolving-Term	161	268
Total	69,017	98,918
Substandard
Total Loan Balance
Current fiscal year	0	584
Year two	1,452	4,561
Year three	13,912	2,487
Year four	4,430	24,589
Year five	33,354	3,196
More than five years	37,542	44,886
Revolving	30,010	26,717
Revolving-Term	4,380	2,740
Total	125,080	109,760
Doubtful
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	366
Year five	0	883
More than five years	0	0
Revolving	1,610	2,901
Revolving-Term	0	0
Total	1,610	4,150
Commercial loans | Commercial real estate
Total Loan Balance
Current fiscal year	480,967	278,187
Year two	315,684	289,081
Year three	326,048	363,529
Year four	319,652	415,621
Year five	343,726	215,632
More than five years	1,093,130	1,110,490
Revolving	42,554	35,991
Revolving-Term	0	0
Total	2,921,761	2,708,531
Year-to-date Gross Charge-offs
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	4,907	0
Year five	0	0
More than five years	2,432	5,205
Revolving	0	0
Revolving-Term	0	0
Total	7,339	5,205
Commercial loans | Commercial and industrial
Total Loan Balance
Current fiscal year	161,634	120,143
Year two	96,065	148,100
Year three	115,559	195,756
Year four	139,784	152,971
Year five	93,561	31,312
More than five years	184,888	197,426
Revolving	539,114	505,929
Revolving-Term	0	0
Total	1,330,605	1,351,637
Year-to-date Gross Charge-offs
Current fiscal year	256	0
Year two	0	78
Year three	4,014	0
Year four	172	1,235
Year five	0	0
More than five years	2,089	91
Revolving	192	1,032
Revolving-Term	0	0
Total	6,723	2,436
Commercial loans | Commercial construction
Total Loan Balance
Current fiscal year	172,822	119,355
Year two	119,821	121,816
Year three	43,093	73,851
Year four	18,762	14,911
Year five	2,520	884
More than five years	1,260	2,139
Revolving	7,099	8,310
Revolving-Term	0	0
Total	365,377	341,266
Year-to-date Gross Charge-offs
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	118	0
Year five	0	0
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	118	0
Commercial loans | Business banking
Total Loan Balance
Current fiscal year	182,401	149,624
Year two	132,590	233,041
Year three	206,281	226,654
Year four	199,780	177,683
Year five	161,293	76,643
More than five years	338,580	345,327
Revolving	93,856	92,981
Revolving-Term	1,082	1,305
Total	1,315,863	1,303,258
Year-to-date Gross Charge-offs
Current fiscal year	0	0
Year two	19	79
Year three	132	124
Year four	39	0
Year five	225	56
More than five years	699	1,486
Revolving	0	0
Revolving-Term	0	0
Total	1,114	1,745
Commercial loans | Pass | Commercial real estate
Total Loan Balance
Current fiscal year	480,967	278,187
Year two	312,777	287,081
Year three	322,165	362,174
Year four	311,087	413,781
Year five	328,936	213,384
More than five years	1,047,543	1,040,703
Revolving	42,300	35,737
Revolving-Term	0	0
Total	2,845,775	2,631,047
Commercial loans | Pass | Commercial and industrial
Total Loan Balance
Current fiscal year	161,634	119,580
Year two	95,715	147,007
Year three	111,222	194,363
Year four	138,390	131,877
Year five	75,406	30,093
More than five years	165,633	175,359
Revolving	501,472	466,640
Revolving-Term	0	0
Total	1,249,472	1,264,919
Commercial loans | Pass | Commercial construction
Total Loan Balance
Current fiscal year	172,822	119,355
Year two	118,952	121,816
Year three	43,093	57,853
Year four	18,762	14,911
Year five	2,520	884
More than five years	1,260	2,139
Revolving	7,099	8,310
Revolving-Term	0	0
Total	364,508	325,268
Commercial loans | Pass | Business banking
Total Loan Balance
Current fiscal year	182,401	149,603
Year two	132,196	230,784
Year three	201,106	225,318
Year four	197,145	173,763
Year five	157,792	76,087
More than five years	328,135	332,707
Revolving	93,701	92,756
Revolving-Term	453	597
Total	1,292,929	1,281,615
Commercial loans | Special mention | Commercial real estate
Total Loan Balance
Current fiscal year	0	0
Year two	2,907	2,000
Year three	0	370
Year four	6,865	1,840
Year five	3,148	0
More than five years	25,805	46,104
Revolving	254	254
Revolving-Term	0	0
Total	38,979	50,568
Commercial loans | Special mention | Commercial and industrial
Total Loan Balance
Current fiscal year	0	0
Year two	350	20
Year three	2,423	1,221
Year four	1,394	142
Year five	3	10
More than five years	13,611	14,896
Revolving	8,179	11,033
Revolving-Term	0	0
Total	25,960	27,322
Commercial loans | Special mention | Commercial construction
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	15,998
Year four	0	0
Year five	0	0
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	0	15,998
Commercial loans | Special mention | Business banking
Total Loan Balance
Current fiscal year	0	0
Year two	394	0
Year three	0	49
Year four	427	130
Year five	137	147
More than five years	2,871	4,302
Revolving	4	35
Revolving-Term	161	268
Total	3,994	4,931
Commercial loans | Substandard | Commercial real estate
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	3,883	985
Year four	1,700	0
Year five	11,642	1,834
More than five years	19,782	23,683
Revolving	0	0
Revolving-Term	0	0
Total	37,007	26,502
Commercial loans | Substandard | Commercial and industrial
Total Loan Balance
Current fiscal year	0	563
Year two	0	1,073
Year three	1,914	172
Year four	0	20,586
Year five	18,152	740
More than five years	5,644	7,171
Revolving	27,853	25,355
Revolving-Term	0	0
Total	53,563	55,660
Commercial loans | Substandard | Commercial construction
Total Loan Balance
Current fiscal year	0	0
Year two	869	0
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	869	0
Commercial loans | Substandard | Business banking
Total Loan Balance
Current fiscal year	0	21
Year two	0	2,257
Year three	5,175	1,287
Year four	2,208	3,790
Year five	3,364	409
More than five years	7,574	8,318
Revolving	151	190
Revolving-Term	468	440
Total	18,940	16,712
Commercial loans | Doubtful | Commercial real estate
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	414
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	0	414
Commercial loans | Doubtful | Commercial and industrial
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	366
Year five	0	469
More than five years	0	0
Revolving	1,610	2,901
Revolving-Term	0	0
Total	1,610	3,736
Commercial loans | Doubtful | Commercial construction
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	0	0
Commercial loans | Doubtful | Business banking
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	0	0
Consumer loans | Consumer real estate
Total Loan Balance
Current fiscal year	161,896	217,250
Year two	221,288	335,763
Year three	300,460	324,389
Year four	306,962	133,347
Year five	119,961	95,504
More than five years	281,990	229,462
Revolving	620,773	570,558
Revolving-Term	33,741	27,236
Total	2,047,071	1,933,509
Year-to-date Gross Charge-offs
Current fiscal year	5	0
Year two	35	0
Year three	134	0
Year four	2	0
Year five	0	9
More than five years	156	37
Revolving	31	86
Revolving-Term	465	1,216
Total	828	1,348
Consumer loans | Other consumer
Total Loan Balance
Current fiscal year	7,016	8,456
Year two	5,253	6,849
Year three	3,932	7,349
Year four	3,869	3,249
Year five	1,100	1,768
More than five years	1,127	618
Revolving	59,304	71,039
Revolving-Term	9,679	5,429
Total	91,280	104,757
Year-to-date Gross Charge-offs
Current fiscal year	1,027	839
Year two	35	34
Year three	36	164
Year four	73	103
Year five	30	26
More than five years	58	18
Revolving	1	0
Revolving-Term	693	270
Total	1,953	1,454
Consumer loans | Pass | Consumer real estate
Total Loan Balance
Current fiscal year	161,896	217,250
Year two	220,705	334,532
Year three	297,533	324,346
Year four	306,440	133,155
Year five	119,775	95,301
More than five years	277,507	223,799
Revolving	618,767	569,386
Revolving-Term	29,868	24,940
Total	2,032,491	1,922,709
Consumer loans | Pass | Other consumer
Total Loan Balance
Current fiscal year	7,016	8,456
Year two	5,253	6,849
Year three	3,919	7,349
Year four	3,869	3,228
Year five	1,090	1,758
More than five years	984	468
Revolving	59,304	71,039
Revolving-Term	9,640	5,425
Total	91,075	104,572
Consumer loans | Special mention | Consumer real estate
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	84	99
Revolving	0	0
Revolving-Term	0	0
Total	84	99
Consumer loans | Special mention | Other consumer
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	0	0
Consumer loans | Substandard | Consumer real estate
Total Loan Balance
Current fiscal year	0	0
Year two	583	1,231
Year three	2,927	43
Year four	522	192
Year five	186	203
More than five years	4,399	5,564
Revolving	2,006	1,172
Revolving-Term	3,873	2,296
Total	14,496	10,701
Consumer loans | Substandard | Other consumer
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	13	0
Year four	0	21
Year five	10	10
More than five years	143	150
Revolving	0	0
Revolving-Term	39	4
Total	205	185
Consumer loans | Doubtful | Consumer real estate
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	0	0
Consumer loans | Doubtful | Other consumer
Total Loan Balance
Current fiscal year	0	0
Year two	0	0
Year three	0	0
Year four	0	0
Year five	0	0
More than five years	0	0
Revolving	0	0
Revolving-Term	0	0
Total	$ 0	$ 0