Loans and Allowance for Credit Losses - Schedule of Changes in Allowance for Loan Losses by Loan Category (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 327,892	$ 224,310	$ 331,841	$ 228,952
Initial reserve on purchased seasoned loans	487		487
Charge-offs	(12,931)	(3,400)	(25,849)	(15,887)
Recoveries	3,151	3,603	6,364	4,848
Provision (release)	6,755	7,600	12,511	14,200
Ending balance	325,354	232,113	325,354	232,113
Commercial and industrial \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	59,508	46,490	65,768	41,090
Initial reserve on purchased seasoned loans	487		487
Charge-offs	(816)	(82)	(7,316)	(82)
Recoveries	794	7	1,588	18
Provision (release)	3,236	7,695	2,682	13,084
Ending balance	63,209	54,110	63,209	54,110
Commercial real estate \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	178,826	106,634	164,376	116,175
Initial reserve on purchased seasoned loans	0		0
Charge-offs	(9,202)	(1,790)	(12,790)	(13,377)
Recoveries	946	2,368	946	3,062
Provision (release)	1,769	(2,122)	19,807	(770)
Ending balance	172,339	105,090	172,339	105,090
Commercial construction \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	11,123	8,514	21,058	8,462
Initial reserve on purchased seasoned loans	0		0
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision (release)	1,128	812	(8,807)	864
Ending balance	12,251	9,326	12,251	9,326
Business banking \| Commercial Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	22,159	20,315	22,921	19,899
Initial reserve on purchased seasoned loans	0		0
Charge-offs	(2,040)	(999)	(4,254)	(1,341)
Recoveries	1,213	942	3,343	1,264
Provision (release)	1,839	427	1,161	863
Ending balance	23,171	20,685	23,171	20,685
Residential real estate \| Residential Real Estate
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	42,641	31,096	44,177	32,291
Initial reserve on purchased seasoned loans	0		0
Charge-offs	(68)	0	(68)	0
Recoveries	40	36	72	75
Provision (release)	(2,028)	349	(3,596)	(885)
Ending balance	40,585	31,481	40,585	31,481
Consumer home equity \| Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	9,627	6,891	9,171	7,472
Initial reserve on purchased seasoned loans	0		0
Charge-offs	(3)	0	(7)	0
Recoveries	1	5	64	5
Provision (release)	695	184	1,092	(397)
Ending balance	10,320	7,080	10,320	7,080
Other Consumer \| Consumer Portfolio Segment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,008	4,370	4,370	3,563
Initial reserve on purchased seasoned loans	0		0
Charge-offs	(802)	(529)	(1,414)	(1,087)
Recoveries	157	245	351	424
Provision (release)	116	255	172	1,441
Ending balance	$ 3,479	$ 4,341	$ 3,479	$ 4,341

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
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-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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Amount of increase in allowance for credit loss for financing receivable from purchased seasoned loan.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-Paragraph 13
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-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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