Loans and Allowance for Credit Losses - Loan Balances by Year of Origination and Performing and Nonperforming Status (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	$ 298,890	$ 893,015
Year two	901,514	1,134,650
Year three	1,087,612	1,191,528
Year four	1,165,428	897,782
Year five	876,014	421,743
More than five years	2,188,191	1,885,462
Revolving	1,282,043	1,284,808
Revolving-Term	36,657	33,970
Total	7,836,349	7,742,958
Commercial Loans \| Commercial real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	146,775	278,187
Year two	270,301	289,081
Year three	296,522	363,529
Year four	351,124	415,621
Year five	412,182	215,632
More than five years	1,254,645	1,110,490
Revolving	44,516	35,991
Revolving-Term	0	0
Total	2,776,065	2,708,531
Commercial Loans \| Commercial and industrial
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	27,389	120,143
Year two	123,508	148,100
Year three	136,108	195,756
Year four	192,902	152,971
Year five	145,744	31,312
More than five years	209,881	197,426
Revolving	495,559	505,929
Revolving-Term	0	0
Total	1,331,091	1,351,637
Commercial Loans \| Commercial construction
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	36,944	119,355
Year two	131,909	121,816
Year three	104,310	73,851
Year four	72,631	14,911
Year five	13,054	884
More than five years	2,111	2,139
Revolving	6,910	8,310
Revolving-Term	0	0
Total	367,869	341,266
Commercial Loans \| Business banking
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	46,684	149,624
Year two	147,247	233,041
Year three	225,252	226,654
Year four	220,919	177,683
Year five	172,626	76,643
More than five years	404,821	345,327
Revolving	95,875	92,981
Revolving-Term	1,058	1,305
Total	1,314,482	1,303,258
Consumer Loans \| Consumer real estate
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	38,600	217,250
Year two	221,466	335,763
Year three	319,479	324,389
Year four	321,530	133,347
Year five	129,810	95,504
More than five years	314,803	229,462
Revolving	573,994	570,558
Revolving-Term	28,995	27,236
Total	1,948,677	1,933,509
Consumer Loans \| Other consumer
Financing Receivable, Credit Quality Indicator [Line Items]
Current fiscal year	2,498	8,456
Year two	7,083	6,849
Year three	5,941	7,349
Year four	6,322	3,249
Year five	2,598	1,768
More than five years	1,930	618
Revolving	65,189	71,039
Revolving-Term	6,604	5,429
Total	$ 98,165	$ 104,757

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

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