Impaired Loans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	$ 19,197	$ 17,689
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	19,491	18,400
Specific valuation allowance	3,223	5,223
Loans with a Specific Valuation Allowance, Average Balance	19,519	18,986
Loans without a Specific Valuation Allowance, Recorded Balance	89,591	102,305
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	107,486	122,833
Loans without a Specific Valuation Allowance, Average Balance	106,747	107,945
Recorded balance	108,788	119,994
Unpaid principal balance	126,977	141,233
Average balance	126,266	126,931
Residential Real Estate | Residential Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	1,957	2,978
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	2,220	3,046
Specific valuation allowance	83	246
Loans with a Specific Valuation Allowance, Average Balance	2,686	2,928
Loans without a Specific Valuation Allowance, Recorded Balance	10,728	9,421
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	11,989	10,380
Loans without a Specific Valuation Allowance, Average Balance	10,269	9,834
Recorded balance	12,685	12,399
Unpaid principal balance	14,209	13,426
Average balance	12,955	12,762
Commercial | Commercial Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	9,345	4,545
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	9,345	4,573
Specific valuation allowance	568	500
Loans with a Specific Valuation Allowance, Average Balance	8,498	5,851
Loans without a Specific Valuation Allowance, Recorded Balance	59,492	72,991
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	71,300	89,839
Loans without a Specific Valuation Allowance, Average Balance	73,889	76,427
Recorded balance	68,837	77,536
Unpaid principal balance	80,645	94,412
Average balance	82,387	82,278
Commercial | Other Commercial
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	7,268	8,183
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	7,268	8,378
Specific valuation allowance	2,313	3,851
Loans with a Specific Valuation Allowance, Average Balance	7,081	8,477
Loans without a Specific Valuation Allowance, Recorded Balance	13,707	14,849
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	17,689	16,931
Loans without a Specific Valuation Allowance, Average Balance	17,376	15,129
Recorded balance	20,975	23,032
Unpaid principal balance	24,957	25,309
Average balance	24,457	23,606
Consumer and Other | Home Equity
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	120	186
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	120	199
Specific valuation allowance	39	56
Loans with a Specific Valuation Allowance, Average Balance	82	359
Loans without a Specific Valuation Allowance, Recorded Balance	3,377	3,569
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	3,986	4,098
Loans without a Specific Valuation Allowance, Average Balance	3,465	4,734
Recorded balance	3,497	3,755
Unpaid principal balance	4,106	4,297
Average balance	3,547	5,093
Consumer and Other | Other Consumer
Summary of the impaired loans by portfolio class of loans
Loans with a Specific Valuation Allowance, Recorded Balance	507	1,797
Loans with a Specific Valuation Allowance, Unpaid Principal Balance	538	2,204
Specific valuation allowance	220	570
Loans with a Specific Valuation Allowance, Average Balance	1,172	1,371
Loans without a Specific Valuation Allowance, Recorded Balance	2,287	1,475
Loans without a Specific Valuation Allowance, Unpaid Principal Balance	2,522	1,585
Loans without a Specific Valuation Allowance, Average Balance	1,748	1,821
Recorded balance	2,794	3,272
Unpaid principal balance	3,060	3,789
Average balance	$ 2,920	$ 3,192