Loans and Allowance for Credit Losses - Allowance for Credit Loss Activity (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 93,178	$ 101,494	$ 101,494
Provision for credit losses on loans	1,780	(2,511)
Charge-offs	(1,935)	(884)	(18,075)
Recoveries	248	911
Net Recoveries (Charge-offs)	(1,687)	27
Balance at End of Period	93,271	99,010	93,178
Commercial loans | Commercial real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	29,357	30,254	30,254
Provision for credit losses on loans	(974)	(493)
Charge-offs	0	0	(7,339)
Recoveries	2	134
Net Recoveries (Charge-offs)	2	134
Balance at End of Period	28,385	29,895	29,357
Commercial loans | Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	29,142	37,084	37,084
Provision for credit losses on loans	1,684	(3,643)
Charge-offs	(198)	(172)	(6,723)
Recoveries	65	145
Net Recoveries (Charge-offs)	(133)	(27)
Balance at End of Period	30,693	33,414	29,142
Commercial loans | Commercial construction
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	4,400	4,893	4,893
Provision for credit losses on loans	253	1,017
Charge-offs	0	(30)	(118)
Recoveries	0	0
Net Recoveries (Charge-offs)	0	(30)
Balance at End of Period	4,653	5,880	4,400
Commercial loans | Business banking
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	11,335	10,681	10,681
Provision for credit losses on loans	120	650
Charge-offs	(554)	(143)	(1,114)
Recoveries	18	25
Net Recoveries (Charge-offs)	(536)	(118)
Balance at End of Period	10,919	11,213	11,335
Consumer loans | Consumer real estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	16,297	15,776	15,776
Provision for credit losses on loans	147	160
Charge-offs	(301)	(162)	(828)
Recoveries	38	133
Net Recoveries (Charge-offs)	(263)	(29)
Balance at End of Period	16,181	15,907	16,297
Consumer loans | Other consumer
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	2,647	2,806	2,806
Provision for credit losses on loans	550	(202)
Charge-offs	(882)	(377)	(1,953)
Recoveries	125	474
Net Recoveries (Charge-offs)	(757)	97
Balance at End of Period	$ 2,440	$ 2,701	$ 2,647