Business Segment Reporting - Schedule of Noninterest Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Segment Reporting Information [Line Items]
Mortgage banking revenue	$ 39,571	$ 42,080
Investment securities losses, net	(6,811)	(36,661)
Other (loss) income	(6,917)	9,667
Total other income	231,694	210,390
Corporate And Eliminations
Segment Reporting Information [Line Items]
Mortgage banking revenue	0	0
Investment securities losses, net	(6,811)	(36,661)
Other (loss) income	4,445	7,588
Total other income	197	(27,010)
Service charges and commissions
Segment Reporting Information [Line Items]
Revenue	57,631	56,137
Service charges and commissions \| Corporate And Eliminations
Segment Reporting Information [Line Items]
Revenue	435	440
Service Revenue
Segment Reporting Information [Line Items]
Revenue	67,570	67,531
Service Revenue \| Corporate And Eliminations
Segment Reporting Information [Line Items]
Revenue	97	105
Brokerage services
Segment Reporting Information [Line Items]
Revenue	28,696	25,739
Brokerage services \| Corporate And Eliminations
Segment Reporting Information [Line Items]
Revenue	2,452	2,124
Fees for fiduciary services
Segment Reporting Information [Line Items]
Revenue	51,954	45,897
Fees for fiduciary services \| Corporate And Eliminations
Segment Reporting Information [Line Items]
Revenue	(421)	(606)
Consumer
Segment Reporting Information [Line Items]
Loss on sale of portfolio	13,600
Consumer \| Operating Segments
Segment Reporting Information [Line Items]
Mortgage banking revenue	39,571	42,080
Investment securities losses, net	0	0
Other (loss) income	(11,853)	1,210
Total other income	111,268	124,854
Consumer \| Service charges and commissions \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	39,005	38,248
Consumer \| Service Revenue \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	44,629	43,358
Consumer \| Brokerage services \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	(84)	(42)
Consumer \| Fees for fiduciary services \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	0	0
Commercial \| Operating Segments
Segment Reporting Information [Line Items]
Mortgage banking revenue	0	0
Investment securities losses, net	0	0
Other (loss) income	488	566
Total other income	42,869	43,334
Commercial \| Service charges and commissions \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	18,191	17,449
Commercial \| Service Revenue \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	22,844	24,068
Commercial \| Brokerage services \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	1,346	1,251
Commercial \| Fees for fiduciary services \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	0	0
Wealth Management \| Operating Segments
Segment Reporting Information [Line Items]
Mortgage banking revenue	0	0
Investment securities losses, net	0	0
Other (loss) income	3	303
Total other income	77,360	69,212
Wealth Management \| Service charges and commissions \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	0	0
Wealth Management \| Service Revenue \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	0	0
Wealth Management \| Brokerage services \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	24,982	22,406
Wealth Management \| Fees for fiduciary services \| Operating Segments
Segment Reporting Information [Line Items]
Revenue	$ 52,375	$ 46,503

Amount of unrealized and realized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity), investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and investment in debt security measured at fair value with change in fair value recognized in net income (trading).

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