Loans and Allowance for Credit Losses - Loan Balances by Year of Origination and Performing and Nonperforming Status (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	$ 567,185	$ 893,015
Year two	900,274	1,134,650
Year three	1,061,781	1,191,528
Year four	1,124,721	897,782
Year five	831,096	421,743
More than five years	2,074,958	1,885,462
Revolving	1,334,790	1,284,808
Revolving-Term	39,629	33,970
Total	7,934,434	7,742,958
Commercial Loans \| Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	256,433	278,187
Year two	283,027	289,081
Year three	296,050	363,529
Year four	353,480	415,621
Year five	388,471	215,632
More than five years	1,203,975	1,110,490
Revolving	43,037	35,991
Revolving-Term	0	0
Total	2,824,473	2,708,531
Commercial Loans \| Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	56,481	120,143
Year two	116,947	148,100
Year three	125,718	195,756
Year four	178,689	152,971
Year five	129,992	31,312
More than five years	186,727	197,426
Revolving	526,098	505,929
Revolving-Term	0	0
Total	1,320,652	1,351,637
Commercial Loans \| Commercial construction
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	79,460	119,355
Year two	128,037	121,816
Year three	101,433	73,851
Year four	56,394	14,911
Year five	12,273	884
More than five years	1,358	2,139
Revolving	7,284	8,310
Revolving-Term	0	0
Total	386,239	341,266
Commercial Loans \| Business banking
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	95,474	149,624
Year two	142,410	233,041
Year three	219,575	226,654
Year four	214,311	177,683
Year five	170,102	76,643
More than five years	380,726	345,327
Revolving	95,699	92,981
Revolving-Term	1,113	1,305
Total	1,319,410	1,303,258
Consumer Loans \| Consumer real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	75,177	217,250
Year two	223,416	335,763
Year three	313,759	324,389
Year four	316,323	133,347
Year five	128,238	95,504
More than five years	300,592	229,462
Revolving	593,255	570,558
Revolving-Term	32,723	27,236
Total	1,983,483	1,933,509
Consumer Loans \| Other consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	4,160	8,456
Year two	6,437	6,849
Year three	5,246	7,349
Year four	5,524	3,249
Year five	2,020	1,768
More than five years	1,580	618
Revolving	69,417	71,039
Revolving-Term	5,793	5,429
Total	$ 100,177	$ 104,757

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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