Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
Total	$ 8,071,957	$ 7,742,958
Nonaccrual	55,558	27,937	$ 22,947
Current
Financing Receivable, Past Due [Line Items]
Total	8,003,815	7,703,543
Total Past Due Loans
Financing Receivable, Past Due [Line Items]
Total	68,142	39,415
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total	5,195	5,431
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total	7,389	6,047
Commercial loans | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	2,921,761	2,708,531
Nonaccrual	15,185	3,228	6,320
Commercial loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	1,330,605	1,351,637
Nonaccrual	24,906	11,173	878
Commercial loans | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	365,377	341,266
Nonaccrual	869	0	4,960
Commercial loans | Business banking
Financing Receivable, Past Due [Line Items]
Total	1,315,863	1,303,258
Nonaccrual	3,576	2,988	4,147
Commercial loans | Current | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	2,906,576	2,705,303
Commercial loans | Current | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	1,305,388	1,338,053
Commercial loans | Current | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	364,508	340,230
Commercial loans | Current | Business banking
Financing Receivable, Past Due [Line Items]
Total	1,308,368	1,297,651
Commercial loans | Total Past Due Loans | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	15,185	3,228
Commercial loans | Total Past Due Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	25,217	13,584
Commercial loans | Total Past Due Loans | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	869	1,036
Commercial loans | Total Past Due Loans | Business banking
Financing Receivable, Past Due [Line Items]
Total	7,495	5,607
Commercial loans | 30-59 Days Past Due | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	0	0
Commercial loans | 30-59 Days Past Due | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	311	415
Commercial loans | 30-59 Days Past Due | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	0	0
Commercial loans | 30-59 Days Past Due | Business banking
Financing Receivable, Past Due [Line Items]
Total	999	2,336
Commercial loans | 60-89 Days Past Due | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	0	0
Commercial loans | 60-89 Days Past Due | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	0	1,996
Commercial loans | 60-89 Days Past Due | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	0	1,036
Commercial loans | 60-89 Days Past Due | Business banking
Financing Receivable, Past Due [Line Items]
Total	2,920	283
Consumer loans | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	2,047,071	1,933,509
Nonaccrual	10,864	10,318	6,312
Consumer loans | Other consumer
Financing Receivable, Past Due [Line Items]
Total	91,280	104,757
Nonaccrual	158	230	$ 330
Consumer loans | Current | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	2,028,472	1,918,150
Consumer loans | Current | Other consumer
Financing Receivable, Past Due [Line Items]
Total	90,503	104,156
Consumer loans | Total Past Due Loans | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	18,599	15,359
Consumer loans | Total Past Due Loans | Other consumer
Financing Receivable, Past Due [Line Items]
Total	777	601
Consumer loans | 30-59 Days Past Due | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	3,281	2,464
Consumer loans | 30-59 Days Past Due | Other consumer
Financing Receivable, Past Due [Line Items]
Total	604	216
Consumer loans | 60-89 Days Past Due | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	4,454	2,577
Consumer loans | 60-89 Days Past Due | Other consumer
Financing Receivable, Past Due [Line Items]
Total	$ 15	$ 155