Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	$ 5,638	$ 5,638	$ 19,197
Loans with a specific valuation allowance, Unpaid principal balance	5,640	5,640	19,491
Specific valuation allowance	108	108	3,223
Loans with a specific valuation allowance, Average balance	10,850	13,632	19,519
Loans without a specific valuation allowance, Recorded balance	96,343	96,343	89,591
Loans without a specific valuation allowance, Unpaid principal balance	113,211	113,211	107,486
Loans without a specific valuation allowance, Average balance	92,346	91,428	106,747
Recorded balance	101,981	101,981	108,788
Unpaid principal balance	118,851	118,851	126,977
Average balance	103,196	105,060	126,266
Residential Real Estate | Residential Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	43	43	1,957
Loans with a specific valuation allowance, Unpaid principal balance	43	43	2,220
Specific valuation allowance	0	0	83
Loans with a specific valuation allowance, Average balance	44	681	2,686
Loans without a specific valuation allowance, Recorded balance	10,739	10,739	10,728
Loans without a specific valuation allowance, Unpaid principal balance	12,004	12,004	11,989
Loans without a specific valuation allowance, Average balance	10,670	10,690	10,269
Recorded balance	10,782	10,782	12,685
Unpaid principal balance	12,047	12,047	14,209
Average balance	10,714	11,371	12,955
Commercial | Commercial Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	5,474	5,474	9,345
Loans with a specific valuation allowance, Unpaid principal balance	5,474	5,474	9,345
Specific valuation allowance	38	38	568
Loans with a specific valuation allowance, Average balance	5,739	6,941	8,498
Loans without a specific valuation allowance, Recorded balance	57,465	57,465	59,492
Loans without a specific valuation allowance, Unpaid principal balance	68,852	68,852	71,300
Loans without a specific valuation allowance, Average balance	58,283	58,686	73,889
Recorded balance	62,939	62,939	68,837
Unpaid principal balance	74,326	74,326	80,645
Average balance	64,022	65,627	82,387
Commercial | Other Commercial
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	100	100	7,268
Loans with a specific valuation allowance, Unpaid principal balance	102	102	7,268
Specific valuation allowance	68	68	2,313
Loans with a specific valuation allowance, Average balance	5,052	5,791	7,081
Loans without a specific valuation allowance, Recorded balance	22,050	22,050	13,707
Loans without a specific valuation allowance, Unpaid principal balance	25,363	25,363	17,689
Loans without a specific valuation allowance, Average balance	17,500	16,236	17,376
Recorded balance	22,150	22,150	20,975
Unpaid principal balance	25,465	25,465	24,957
Average balance	22,552	22,027	24,457
Consumer and Other | Home Equity
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	0	0	120
Loans with a specific valuation allowance, Unpaid principal balance	0	0	120
Specific valuation allowance	0	0	39
Loans with a specific valuation allowance, Average balance	0	40	82
Loans without a specific valuation allowance, Recorded balance	3,221	3,221	3,377
Loans without a specific valuation allowance, Unpaid principal balance	3,857	3,857	3,986
Loans without a specific valuation allowance, Average balance	3,139	3,218	3,465
Recorded balance	3,221	3,221	3,497
Unpaid principal balance	3,857	3,857	4,106
Average balance	3,139	3,258	3,547
Consumer and Other | Other Consumer
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	21	21	507
Loans with a specific valuation allowance, Unpaid principal balance	21	21	538
Specific valuation allowance	2	2	220
Loans with a specific valuation allowance, Average balance	15	179	1,172
Loans without a specific valuation allowance, Recorded balance	2,868	2,868	2,287
Loans without a specific valuation allowance, Unpaid principal balance	3,135	3,135	2,522
Loans without a specific valuation allowance, Average balance	2,754	2,598	1,748
Recorded balance	2,889	2,889	2,794
Unpaid principal balance	3,156	3,156	3,060
Average balance	$ 2,769	$ 2,777	$ 2,920