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, 2025	Mar. 31, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 228,952	$ 148,993
Charge-offs	(12,487)	(8,015)
Recoveries	1,245	761
Provision (release)	6,600	7,451
Ending balance	224,310	149,190
Commercial and industrial \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	41,090	26,959
Charge-offs	0	0
Recoveries	11	25
Provision (release)	5,389	1,879
Ending balance	46,490	28,863
Commercial real estate \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	116,175	65,475
Charge-offs	(11,587)	(7,250)
Recoveries	694	132
Provision (release)	1,352	6,272
Ending balance	106,634	64,629
Commercial construction \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	8,462	6,666
Charge-offs	0	0
Recoveries	0	0
Provision (release)	52	(462)
Ending balance	8,514	6,204
Business banking \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	19,899	14,913
Charge-offs	(342)	(102)
Recoveries	322	410
Provision (release)	436	(590)
Ending balance	20,315	14,631
Residential real estate \| Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	32,291	25,954
Charge-offs	0	(10)
Recoveries	39	31
Provision (release)	(1,234)	(40)
Ending balance	31,096	25,935
Consumer home equity \| Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	7,472	5,595
Charge-offs	0	(2)
Recoveries	0	0
Provision (release)	(581)	91
Ending balance	6,891	5,684
Other Consumer \| Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	3,563	3,431
Charge-offs	(558)	(651)
Recoveries	179	163
Provision (release)	1,186	301
Ending balance	$ 4,370	$ 3,244

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 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

Reference 2: 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

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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 (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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