Loans and Leases, Changes in Allowance for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	$ 68,573	$ 61,032	$ 66,885	$ 61,007
Provision / (recapture) for credit losses	2,500	1,107	4,000	1,107
Charge-offs	(9)	(285)	(32)	(294)
Recoveries	48	226	259	260
Net (charge-offs) / recoveries	39	(59)	227	(34)
Balance at end of period	71,112	62,080	71,112	62,080
Cumulative Effect, Period of Adoption, Adjustment [Member] | ASC 326 [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period				0
Commercial & Agricultural R/E [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	32,694	32,511	32,551	38,149
Provision / (recapture) for credit losses	2,001	2,205	1,974	2,757
Charge-offs	0	0	0	0
Recoveries	0	0	170	0
Net (charge-offs) / recoveries	0	0	170	0
Balance at end of period	34,695	34,716	34,695	34,716
Commercial & Agricultural R/E [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | ASC 326 [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period				(6,190)
Construction [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	2,785	3,777	3,026	1,456
Provision / (recapture) for credit losses	410	(901)	169	(435)
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Net (charge-offs) / recoveries	0	0	0	0
Balance at end of period	3,195	2,876	3,195	2,876
Construction [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | ASC 326 [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period				1,855
Residential & Home Equity [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	7,334	6,759	7,508	2,847
Provision / (recapture) for credit losses	(176)	10	(346)	876
Charge-offs	0	0	(14)	0
Recoveries	21	105	31	119
Net (charge-offs) / recoveries	21	105	17	119
Balance at end of period	7,179	6,874	7,179	6,874
Residential & Home Equity [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | ASC 326 [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period				3,032
Commercial & Agricultural [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	23,888	16,098	21,705	16,954
Provision / (recapture) for credit losses	285	(131)	2,448	(1,831)
Charge-offs	0	(276)	0	(276)
Recoveries	21	117	41	135
Net (charge-offs) / recoveries	21	(159)	41	(141)
Balance at end of period	24,194	15,808	24,194	15,808
Commercial & Agricultural [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | ASC 326 [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period				826
Commercial Leases [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	1,720	1,466	1,924	938
Provision / (recapture) for credit losses	(63)	179	(267)	78
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Net (charge-offs) / recoveries	0	0	0	0
Balance at end of period	1,657	1,645	1,657	1,645
Commercial Leases [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | ASC 326 [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period				629
Consumer and Other [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period	152	421	171	663
Provision / (recapture) for credit losses	43	(255)	22	(338)
Charge-offs	(9)	(9)	(18)	(18)
Recoveries	6	4	17	6
Net (charge-offs) / recoveries	(3)	(5)	(1)	(12)
Balance at end of period	$ 192	$ 161	$ 192	161
Consumer and Other [Member] | Cumulative Effect, Period of Adoption, Adjustment [Member] | ASC 326 [Member]
Allowance for Credit Losses [Roll Forward]
Balance at beginning of period				$ (152)