Loans and Allowance for Credit Losses - Schedule of Changes in Allowance for Loan Losses by Loan Category (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 331,841	$ 228,952
Charge-offs	(12,918)	(12,487)
Recoveries	3,213	1,245
(Release) provision	5,756	6,600
Ending balance	327,892	224,310
Commercial and industrial \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	65,768	41,090
Charge-offs	(6,500)	0
Recoveries	794	11
(Release) provision	(554)	5,389
Ending balance	59,508	46,490
Commercial real estate \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	164,376	116,175
Charge-offs	(3,588)	(11,587)
Recoveries	0	694
(Release) provision	18,038	1,352
Ending balance	178,826	106,634
Commercial construction \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	21,058	8,462
Charge-offs	0	0
Recoveries	0	0
(Release) provision	(9,935)	52
Ending balance	11,123	8,514
Business banking \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	22,921	19,899
Charge-offs	(2,214)	(342)
Recoveries	2,130	322
(Release) provision	(678)	436
Ending balance	22,159	20,315
Residential real estate \| Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	44,177	32,291
Charge-offs	0	0
Recoveries	32	39
(Release) provision	(1,568)	(1,234)
Ending balance	42,641	31,096
Consumer home equity \| Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	9,171	7,472
Charge-offs	(4)	0
Recoveries	63	0
(Release) provision	397	(581)
Ending balance	9,627	6,891
Other Consumer \| Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,370	3,563
Charge-offs	(612)	(558)
Recoveries	194	179
(Release) provision	56	1,186
Ending balance	$ 4,008	$ 4,370

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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