Loans, Allowance for Credit Losses and Credit Quality - Finance Receivable Credit Quality Indicators (Details) - USD ($) $ in Thousands		3 Months Ended				9 Months Ended
		Sep. 30, 2023		Sep. 30, 2022		Sep. 30, 2023		Sep. 30, 2022		Dec. 31, 2022
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		$ 1,825,140		$ 2,347,498		$ 1,825,140		$ 2,347,498
2021		2,677,047		2,617,135		2,677,047		2,617,135
2020		2,247,195		1,958,359		2,247,195		1,958,359
2019		1,690,252		1,065,396		1,690,252		1,065,396
2018		841,526		1,069,133		841,526		1,069,133
Prior		3,214,966		2,968,288		3,214,966		2,968,288
Revolving Loans		1,722,920		1,666,287		1,722,920		1,666,287
Revolving converted to Term		5,189		8,254		5,189		8,254
Total loans		14,224,235	[1]			14,224,235	[1]			$ 13,928,675
Total loans		14,224,235		13,700,350		14,224,235		13,700,350		13,928,675
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023						1,836
2022						5,072
2021						22
2020						37
2019						0
Prior						41
Revolving Loans						23,592
Revolving converted to Term						0
Total		6,018		741		30,600		1,992
Commercial And Industrial [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		312,282		296,626		312,282		296,626
2021		195,683		151,496		195,683		151,496
2020		96,402		123,790		96,402		123,790
2019		83,776		69,474		83,776		69,474
2018		46,996		86,866		46,996		86,866
Prior		116,990		23,769		116,990		23,769
Revolving Loans		800,874		792,966		800,874		792,966
Revolving converted to Term		0		3,362		0		3,362
Total loans		1,653,003	[1]			1,653,003	[1]			1,635,103
Total loans		1,653,003		1,548,349	[1]	1,653,003		1,548,349	[1]	1,635,103
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023						0
2022						0
2021						0
2020						0
2019						0
Prior						34
Revolving Loans						23,437
Revolving converted to Term						0
Total		0		0		23,471		0
Commercial And Industrial [Member] | Pass [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022	[2]	303,838		292,601		303,838		292,601
2021	[2]	188,559		149,588		188,559		149,588
2020	[2]	94,714		122,752		94,714		122,752
2019	[2]	73,366		67,591		73,366		67,591
2018	[2]	45,741		82,911		45,741		82,911
Prior	[2]	116,052		22,943		116,052		22,943
Revolving Loans	[2]	737,335		759,390		737,335		759,390
Revolving converted to Term	[2]	0		3,362		0		3,362
Total loans	[1],[2]	1,559,605				1,559,605
Total loans	[1],[2]			1,501,138				1,501,138
Commercial And Industrial [Member] | Potential Weakness [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		6,511		1,540		6,511		1,540
2021		2,417		973		2,417		973
2020		614		1,038		614		1,038
2019		10,278		1,844		10,278		1,844
2018		90		3,955		90		3,955
Prior		132		715		132		715
Revolving Loans		46,706		6,557		46,706		6,557
Revolving converted to Term		0		0		0		0
Total loans	[1]	66,748				66,748
Total loans	[1]			16,622				16,622
Commercial And Industrial [Member] | Definite Weakness Loss Unlikely [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		1,933		2,485		1,933		2,485
2021		4,707		935		4,707		935
2020		1,074		0		1,074		0
2019		132		39		132		39
2018		1,165		0		1,165		0
Prior		806		111		806		111
Revolving Loans		16,833		27,019		16,833		27,019
Revolving converted to Term		0		0		0		0
Total loans	[1]	26,650				26,650
Total loans	[1]			30,589				30,589
Commercial And Industrial [Member] | Partial Loss Probable [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	0				0
Total loans	[1]			0				0
Commercial And Industrial [Member] | Definite Loss [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	0				0
Total loans	[1]			0				0
Commercial Real Estate [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		889,069		982,035		889,069		982,035
2021		1,225,696		1,522,690		1,225,696		1,522,690
2020		1,420,347		1,311,597		1,420,347		1,311,597
2019		1,331,223		789,834		1,331,223		789,834
2018		632,165		819,847		632,165		819,847
Prior		2,328,376		2,203,527		2,328,376		2,203,527
Revolving Loans		68,496		47,317		68,496		47,317
Revolving converted to Term		858		1,070		858		1,070
Total loans		7,896,230	[1]			7,896,230	[1]			7,760,230
Total loans		7,896,230		7,677,917	[1]	7,896,230		7,677,917	[1]	7,760,230
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023						0
2022						5,072
2021						0
2020						0
2019						0
Prior						0
Revolving Loans						0
Revolving converted to Term						0
Total		5,072		62		5,072		62
Commercial Real Estate [Member] | Pass [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		795,830		922,772		795,830		922,772
2021		1,160,497		1,467,370		1,160,497		1,467,370
2020		1,338,792		1,265,711		1,338,792		1,265,711
2019		1,312,240		773,102		1,312,240		773,102
2018		610,009		733,621		610,009		733,621
Prior		2,188,221		1,976,282		2,188,221		1,976,282
Revolving Loans		68,496		47,317		68,496		47,317
Revolving converted to Term		858		1,070		858		1,070
Total loans	[1]	7,474,943				7,474,943
Total loans	[1]			7,187,245				7,187,245
Commercial Real Estate [Member] | Potential Weakness [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		62,572		32,579		62,572		32,579
2021		37,695		53,096		37,695		53,096
2020		57,987		41,164		57,987		41,164
2019		14,662		14,147		14,662		14,147
2018		2,945		68,298		2,945		68,298
Prior		118,830		205,234		118,830		205,234
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	294,691				294,691
Total loans	[1]			414,518				414,518
Commercial Real Estate [Member] | Definite Weakness Loss Unlikely [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		30,667		26,684		30,667		26,684
2021		27,504		2,224		27,504		2,224
2020		23,568		4,722		23,568		4,722
2019		4,321		2,585		4,321		2,585
2018		19,211		17,928		19,211		17,928
Prior		21,325		21,836		21,325		21,836
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	126,596				126,596
Total loans	[1]			75,979				75,979
Commercial Real Estate [Member] | Partial Loss Probable [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		175		0		175
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	0				0
Total loans	[1]			175				175
Commercial Real Estate [Member] | Definite Loss [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	0				0
Total loans	[1]			0				0
Construction Loans [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		169,202		431,396		169,202		431,396
2021		517,297		405,074		517,297		405,074
2020		222,883		234,723		222,883		234,723
2019		9,939		57,768		9,939		57,768
2018		27,304		26,263		27,304		26,263
Prior		1,569		7,844		1,569		7,844
Revolving Loans		17,248		21,457		17,248		21,457
Revolving converted to Term		0		632		0		632
Total loans		965,442	[1]			965,442	[1]			1,154,413
Total loans		965,442		1,185,157	[1]	965,442		1,185,157	[1]	1,154,413
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023						0
2022						0
2021						0
2020						0
2019						0
Prior						0
Revolving Loans						0
Revolving converted to Term						0
Total		0		0		0		0
Construction Loans [Member] | Pass [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		146,278		388,627		146,278		388,627
2021		491,098		392,229		491,098		392,229
2020		201,730		231,336		201,730		231,336
2019		9,939		57,768		9,939		57,768
2018		27,304		26,263		27,304		26,263
Prior		1,569		7,844		1,569		7,844
Revolving Loans		17,248		21,457		17,248		21,457
Revolving converted to Term		0		632		0		632
Total loans	[1]	895,166				895,166
Total loans	[1]			1,126,156				1,126,156
Construction Loans [Member] | Potential Weakness [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		13,484		40,631		13,484		40,631
2021		0		0		0		0
2020		4,823		3,387		4,823		3,387
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	18,307				18,307
Total loans	[1]			44,018				44,018
Construction Loans [Member] | Definite Weakness Loss Unlikely [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		9,440		2,138		9,440		2,138
2021		26,199		12,845		26,199		12,845
2020		16,330		0		16,330		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	51,969				51,969
Total loans	[1]			14,983				14,983
Construction Loans [Member] | Partial Loss Probable [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	0				0
Total loans	[1]			0				0
Construction Loans [Member] | Definite Loss [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	0				0
Total loans	[1]			0				0
Small Business [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		40,980		42,117		40,980		42,117
2021		53,207		46,744		53,207		46,744
2020		40,832		32,804		40,832		32,804
2019		27,209		17,912		27,209		17,912
2018		13,759		10,667		13,759		10,667
Prior		24,259		20,580		24,259		20,580
Revolving Loans		45,089		38,743		45,089		38,743
Revolving converted to Term		0		0		0		0
Total loans		245,335	[1]			245,335	[1]			219,102
Total loans		245,335		209,567	[1]	245,335		209,567	[1]	219,102
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023						0
2022						0
2021						22
2020						37
2019						0
Prior						0
Revolving Loans						140
Revolving converted to Term						0
Total		112		0		199		59
Small Business [Member] | Pass [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		40,551		41,923		40,551		41,923
2021		52,883		46,581		52,883		46,581
2020		40,706		31,968		40,706		31,968
2019		26,759		17,536		26,759		17,536
2018		13,759		10,454		13,759		10,454
Prior		23,458		20,227		23,458		20,227
Revolving Loans		43,759		37,455		43,759		37,455
Revolving converted to Term		0		0		0		0
Total loans	[1]	241,875				241,875
Total loans	[1]			206,144				206,144
Small Business [Member] | Potential Weakness [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		163		0		163
2020		0		394		0		394
2019		155		369		155		369
2018		0		193		0		193
Prior		186		129		186		129
Revolving Loans		295		697		295		697
Revolving converted to Term		0		0		0		0
Total loans	[1]	636				636
Total loans	[1]			1,945				1,945
Small Business [Member] | Definite Weakness Loss Unlikely [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		429		194		429		194
2021		324		0		324		0
2020		126		442		126		442
2019		295		7		295		7
2018		0		20		0		20
Prior		615		224		615		224
Revolving Loans		1,035		591		1,035		591
Revolving converted to Term		0		0		0		0
Total loans	[1]	2,824				2,824
Total loans	[1]			1,478				1,478
Small Business [Member] | Partial Loss Probable [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	0				0
Total loans	[1]			0				0
Small Business [Member] | Definite Loss [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		0		0		0		0
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	0				0
Total loans	[1]			0				0
Residential Real Estate [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		391,340		557,643		391,340		557,643
2021		645,593		426,721		645,593		426,721
2020		409,145		197,214		409,145		197,214
2019		186,469		96,155		186,469		96,155
2018		90,853		97,204		90,853		97,204
Prior		614,702		584,317		614,702		584,317
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans		2,338,102	[1]			2,338,102	[1]			2,035,524
Total loans		2,338,102		1,959,254	[1]	2,338,102		1,959,254	[1]	2,035,524
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023						0
2022						0
2021						0
2020						0
2019						0
Prior						0
Revolving Loans						0
Revolving converted to Term						0
Total		0		0		0		0
Residential Real Estate [Member] | Pass [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		391,121		557,643		391,121		557,643
2021		645,593		426,721		645,593		426,721
2020		408,752		196,538		408,752		196,538
2019		186,334		95,689		186,334		95,689
2018		89,911		96,828		89,911		96,828
Prior		612,878		582,830		612,878		582,830
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	2,334,589				2,334,589
Total loans	[1]			1,956,249				1,956,249
Residential Real Estate [Member] | Default [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		219		0		219		0
2021		0		0		0		0
2020		393		676		393		676
2019		135		466		135		466
2018		942		376		942		376
Prior		1,824		1,487		1,824		1,487
Revolving Loans		0		0		0		0
Revolving converted to Term		0		0		0		0
Total loans	[1]	3,513				3,513
Total loans	[1]			3,005				3,005
Home Equity Loan [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		21,729		37,298		21,729		37,298
2021		39,251		61,898		39,251		61,898
2020		56,216		56,262		56,216		56,262
2019		50,724		32,883		50,724		32,883
2018		30,039		27,906		30,039		27,906
Prior		126,897		124,610		126,897		124,610
Revolving Loans		766,368		743,123		766,368		743,123
Revolving converted to Term		4,331		3,190		4,331		3,190
Total loans	[1]	1,095,555				1,095,555
Total loans		1,095,555		1,087,170	[1]	1,095,555		1,087,170	[1]	$ 1,088,750
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023						0
2022						0
2021						0
2020						0
2019						0
Prior						0
Revolving Loans						0
Revolving converted to Term						0
Total		0		0		0		122
Home Equity Loan [Member] | Pass [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		21,729		37,298		21,729		37,298
2021		39,251		61,898		39,251		61,898
2020		56,216		56,262		56,216		56,262
2019		50,724		32,761		50,724		32,761
2018		30,039		27,906		30,039		27,906
Prior		126,897		124,325		126,897		124,325
Revolving Loans		765,079		741,952		765,079		741,952
Revolving converted to Term		4,190		3,190		4,190		3,190
Total loans	[1]	1,094,125				1,094,125
Total loans	[1]			1,085,592				1,085,592
Home Equity Loan [Member] | Default [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		0		0		0
2020		0		0		0		0
2019		0		122		0		122
2018		0		0		0		0
Prior		0		285		0		285
Revolving Loans		1,289		1,171		1,289		1,171
Revolving converted to Term		141		0		141		0
Total loans	[1]	1,430				1,430
Total loans	[1]			1,578				1,578
Consumer Loan [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		538		383		538		383
2021		320		2,512		320		2,512
2020		1,370		1,969		1,370		1,969
2019		912		1,370		912		1,370
2018		410		380		410		380
Prior		2,173		3,641		2,173		3,641
Revolving Loans		24,845		22,681		24,845		22,681
Revolving converted to Term		0		0		0		0
Total loans	[1]	30,568				30,568
Total loans	[1]			32,936				32,936
Financing Receivable, Allowance for Credit Loss, Writeoff, by Origination Year [Abstract]
2023						1,836
2022						0
2021						0
2020						0
2019						0
Prior						7
Revolving Loans						15
Revolving converted to Term						0
Total						1,858
Consumer Loan [Member] | Pass [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		538		383		538		383
2021		320		2,498		320		2,498
2020		1,370		1,969		1,370		1,969
2019		912		1,370		912		1,370
2018		410		380		410		380
Prior		2,154		3,630		2,154		3,630
Revolving Loans		24,843		22,680		24,843		22,680
Revolving converted to Term		0		0		0		0
Total loans	[1]	30,547				30,547
Total loans	[1]			32,910				32,910
Consumer Loan [Member] | Default [Member]
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
2022		0		0		0		0
2021		0		14		0		14
2020		0		0		0		0
2019		0		0		0		0
2018		0		0		0		0
Prior		19		11		19		11
Revolving Loans		2		1		2		1
Revolving converted to Term		0		0		0		0
Total loans	[1]	21				21
Total loans	[1]			26				26
Loans Insured or Guaranteed by US Government Authorities
Financing Receivable, before Allowance for Credit Loss, by Origination Year [Abstract]
Total loans		$ 5,100		$ 11,100		$ 5,100		$ 11,100

[1] Loan origination dates in the tables above reflect the original origination date, or the date of a material modification of a previously originated loan.(2)Loans originated as part of the Paycheck Protection Program ("PPP") established by the Coronavirus Aid, Relief and Economic Security Act (the "CARES Act") are included within commercial and industrial under the 2021 and 2020 vintage year and "pass" category as these loans are 100% guaranteed by the U.S. Government. Outstanding PPP loans totaled $5.1 million and $11.1 million as of September 30, 2023 and 2022, respectively.

[2] (3)Other consumer portfolio is inclusive of deposit account overdrafts recorded as loan balances and the associated gross write-offs.