Impaired Loans (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019 USD ($)
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	$ 5,388
Loans with a specific valuation allowance, Unpaid principal balance	5,388
Specific valuation allowance	95
Loans with a specific valuation allowance, Average balance	10,378
Loans without a specific valuation allowance, Recorded balance	89,116
Loans without a specific valuation allowance, Unpaid principal balance	99,355
Loans without a specific valuation allowance, Average balance	93,338
Recorded balance	94,504
Unpaid principal balance	104,743
Average balance	103,716
Residential Real Estate | Residential Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	0
Loans with a specific valuation allowance, Unpaid principal balance	0
Specific valuation allowance	0
Loans with a specific valuation allowance, Average balance	409
Loans without a specific valuation allowance, Recorded balance	7,804
Loans without a specific valuation allowance, Unpaid principal balance	9,220
Loans without a specific valuation allowance, Average balance	9,879
Recorded balance	7,804
Unpaid principal balance	9,220
Average balance	10,288
Commercial | Commercial Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	5,343
Loans with a specific valuation allowance, Unpaid principal balance	5,343
Specific valuation allowance	73
Loans with a specific valuation allowance, Average balance	6,341
Loans without a specific valuation allowance, Recorded balance	53,266
Loans without a specific valuation allowance, Unpaid principal balance	57,735
Loans without a specific valuation allowance, Average balance	59,107
Recorded balance	58,609
Unpaid principal balance	63,078
Average balance	65,448
Commercial | Other Commercial
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	10
Loans with a specific valuation allowance, Unpaid principal balance	10
Specific valuation allowance	10
Loans with a specific valuation allowance, Average balance	3,490
Loans without a specific valuation allowance, Recorded balance	21,465
Loans without a specific valuation allowance, Unpaid principal balance	24,758
Loans without a specific valuation allowance, Average balance	18,079
Recorded balance	21,475
Unpaid principal balance	24,768
Average balance	21,569
Consumer and Other | Home Equity
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	0
Loans with a specific valuation allowance, Unpaid principal balance	0
Specific valuation allowance	0
Loans with a specific valuation allowance, Average balance	24
Loans without a specific valuation allowance, Recorded balance	3,745
Loans without a specific valuation allowance, Unpaid principal balance	4,494
Loans without a specific valuation allowance, Average balance	3,486
Recorded balance	3,745
Unpaid principal balance	4,494
Average balance	3,510
Consumer and Other | Other Consumer
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	35
Loans with a specific valuation allowance, Unpaid principal balance	35
Specific valuation allowance	12
Loans with a specific valuation allowance, Average balance	114
Loans without a specific valuation allowance, Recorded balance	2,836
Loans without a specific valuation allowance, Unpaid principal balance	3,148
Loans without a specific valuation allowance, Average balance	2,787
Recorded balance	2,871
Unpaid principal balance	3,183
Average balance	$ 2,901