Loans and Allowance for Credit Losses - Age Analysis of Past Due Loans Segregated by Class of Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	Dec. 31, 2024
Financing Receivable, Past Due [Line Items]
Total	$ 8,058,386	$ 8,071,957
Nonaccrual	40,216	55,558	$ 27,937
Current
Financing Receivable, Past Due [Line Items]
Total	8,004,659	8,003,815
Total Past Due Loans
Financing Receivable, Past Due [Line Items]
Total	53,727	68,142
30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Total	4,437	5,195
60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Total	9,074	7,389
Commercial loans | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	2,784,318	2,921,761
Nonaccrual	6,937	15,185	3,228
Commercial loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	1,408,034	1,330,605
Nonaccrual	16,243	24,906	11,173
Commercial loans | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	466,210	365,377
Nonaccrual	0	869	0
Commercial loans | Business banking
Financing Receivable, Past Due [Line Items]
Total	1,289,133	1,315,863
Nonaccrual	5,018	3,576	2,988
Commercial loans | Current | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	2,773,080	2,906,576
Commercial loans | Current | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	1,391,791	1,305,388
Commercial loans | Current | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	466,210	364,508
Commercial loans | Current | Business banking
Financing Receivable, Past Due [Line Items]
Total	1,281,110	1,308,368
Commercial loans | Total Past Due Loans | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	11,238	15,185
Commercial loans | Total Past Due Loans | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	16,243	25,217
Commercial loans | Total Past Due Loans | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	0	869
Commercial loans | Total Past Due Loans | Business banking
Financing Receivable, Past Due [Line Items]
Total	8,023	7,495
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	0	311
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	711	999
Commercial loans | 60-89 Days Past Due | Commercial real estate
Financing Receivable, Past Due [Line Items]
Total	4,301	0
Commercial loans | 60-89 Days Past Due | Commercial and industrial
Financing Receivable, Past Due [Line Items]
Total	0	0
Commercial loans | 60-89 Days Past Due | Commercial construction
Financing Receivable, Past Due [Line Items]
Total	0	0
Commercial loans | 60-89 Days Past Due | Business banking
Financing Receivable, Past Due [Line Items]
Total	2,294	2,920
Consumer loans | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	2,030,605	2,047,071
Nonaccrual	11,878	10,864	10,318
Consumer loans | Other consumer
Financing Receivable, Past Due [Line Items]
Total	80,086	91,280
Nonaccrual	140	158	$ 230
Consumer loans | Current | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	2,013,568	2,028,472
Consumer loans | Current | Other consumer
Financing Receivable, Past Due [Line Items]
Total	78,900	90,503
Consumer loans | Total Past Due Loans | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	17,037	18,599
Consumer loans | Total Past Due Loans | Other consumer
Financing Receivable, Past Due [Line Items]
Total	1,186	777
Consumer loans | 30-59 Days Past Due | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	2,697	3,281
Consumer loans | 30-59 Days Past Due | Other consumer
Financing Receivable, Past Due [Line Items]
Total	1,029	604
Consumer loans | 60-89 Days Past Due | Consumer real estate
Financing Receivable, Past Due [Line Items]
Total	2,462	4,454
Consumer loans | 60-89 Days Past Due | Other consumer
Financing Receivable, Past Due [Line Items]
Total	$ 17	$ 15