Loans and Allowance for Credit Losses - Schedule of Financing Receivable, Allowance for Credit Loss (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 148,993	$ 142,211
Charge-offs	(8,015)	(911)
Recoveries	761	756
Provision (release)	7,451	25
Ending balance	149,190	140,938
Allowance for loan losses	149,190	140,938
Cumulative effect accounting adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		(1,143)
Allowance for loan losses
Cumulative effect accounting adjustment \| Accounting Standards Update 2022-02
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		(1,100)
Allowance for loan losses
Commercial and industrial \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	26,959	26,859
Charge-offs	0	0
Recoveries	25	139
Provision (release)	1,879	(116)
Ending balance	28,863	26,929
Allowance for loan losses	28,863	26,929
Commercial and industrial \| Commercial Portfolio Segment \| Cumulative effect accounting adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		47
Allowance for loan losses
Commercial real estate \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	65,475	54,730
Charge-offs	(7,250)	0
Recoveries	132	4
Provision (release)	6,272	459
Ending balance	64,629	55,193
Allowance for loan losses	64,629	55,193
Commercial real estate \| Commercial Portfolio Segment \| Cumulative effect accounting adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		0
Allowance for loan losses
Commercial construction \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,666	7,085
Charge-offs	0	0
Recoveries	0	0
Provision (release)	(462)	493
Ending balance	6,204	7,578
Allowance for loan losses	6,204	7,578
Commercial construction \| Commercial Portfolio Segment \| Cumulative effect accounting adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		0
Allowance for loan losses
Business banking \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	14,913	16,189
Charge-offs	(102)	(343)
Recoveries	410	481
Provision (release)	(590)	(1,102)
Ending balance	14,631	15,085
Allowance for loan losses	14,631	15,085
Business banking \| Commercial Portfolio Segment \| Cumulative effect accounting adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		(140)
Allowance for loan losses
Residential real estate \| Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	25,954	28,129
Charge-offs	(10)	0
Recoveries	31	15
Provision (release)	(40)	(165)
Ending balance	25,935	27,130
Allowance for loan losses	25,935	27,130
Residential real estate \| Residential Real Estate \| Cumulative effect accounting adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		(849)
Allowance for loan losses
Consumer home equity \| Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	5,595	6,454
Charge-offs	(2)	(7)
Recoveries	0	1
Provision (release)	91	(65)
Ending balance	5,684	6,182
Allowance for loan losses	5,684	6,182
Consumer home equity \| Consumer Portfolio Segment \| Cumulative effect accounting adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		(201)
Allowance for loan losses
Other Consumer \| Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	3,431	2,765
Charge-offs	(651)	(561)
Recoveries	163	116
Provision (release)	301	521
Ending balance	3,244	2,841
Allowance for loan losses	$ 3,244	2,841
Other Consumer \| Consumer Portfolio Segment \| Cumulative effect accounting adjustment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance		$ 0
Allowance for loan losses

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

No definition available.

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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. 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 (e)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-13

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- Definition

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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- Definition

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

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