Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Jun. 30, 2016	Dec. 31, 2015
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	$ 23,744	$ 23,744	$ 34,683
Loans with a specific valuation allowance, Unpaid principal balance	23,991	23,991	36,157
Specific valuation allowance	4,365	4,365	8,124
Loans with a specific valuation allowance, Average balance	27,688	30,020	36,176
Loans without a specific valuation allowance, Recorded balance	107,059	107,059	106,090
Loans without a specific valuation allowance, Unpaid principal balance	131,848	131,848	132,718
Loans without a specific valuation allowance, Average balance	108,147	107,461	116,356
Recorded balance	130,803	130,803	140,773
Unpaid principal balance	155,839	155,839	168,875
Average balance	135,835	137,481	152,532
Residential Real Estate | Residential Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	3,176	3,176	8,253
Loans with a specific valuation allowance, Unpaid principal balance	3,243	3,243	9,198
Specific valuation allowance	215	215	782
Loans with a specific valuation allowance, Average balance	5,338	6,310	6,393
Loans without a specific valuation allowance, Recorded balance	15,072	15,072	12,514
Loans without a specific valuation allowance, Unpaid principal balance	16,617	16,617	13,969
Loans without a specific valuation allowance, Average balance	14,306	13,709	13,615
Recorded balance	18,248	18,248	20,767
Unpaid principal balance	19,860	19,860	23,167
Average balance	19,644	20,019	20,008
Commercial | Commercial Real Estate
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	10,068	10,068	12,554
Loans with a specific valuation allowance, Unpaid principal balance	10,084	10,084	12,581
Specific valuation allowance	877	877	1,629
Loans with a specific valuation allowance, Average balance	10,073	10,900	15,827
Loans without a specific valuation allowance, Recorded balance	65,671	65,671	73,291
Loans without a specific valuation allowance, Unpaid principal balance	82,908	82,908	94,028
Loans without a specific valuation allowance, Average balance	68,717	70,241	78,684
Recorded balance	75,739	75,739	85,845
Unpaid principal balance	92,992	92,992	106,609
Average balance	78,790	81,141	94,511
Commercial | Other Commercial
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	9,188	9,188	11,923
Loans with a specific valuation allowance, Unpaid principal balance	9,307	9,307	12,335
Specific valuation allowance	2,761	2,761	5,277
Loans with a specific valuation allowance, Average balance	10,669	11,087	11,768
Loans without a specific valuation allowance, Recorded balance	17,945	17,945	11,951
Loans without a specific valuation allowance, Unpaid principal balance	22,932	22,932	15,539
Loans without a specific valuation allowance, Average balance	16,842	15,212	15,479
Recorded balance	27,133	27,133	23,874
Unpaid principal balance	32,239	32,239	27,874
Average balance	27,511	26,299	27,247
Consumer and Other | Home Equity
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	156	156	102
Loans with a specific valuation allowance, Unpaid principal balance	165	165	109
Specific valuation allowance	118	118	64
Loans with a specific valuation allowance, Average balance	306	238	426
Loans without a specific valuation allowance, Recorded balance	6,286	6,286	6,391
Loans without a specific valuation allowance, Unpaid principal balance	7,221	7,221	7,153
Loans without a specific valuation allowance, Average balance	6,194	6,259	6,350
Recorded balance	6,442	6,442	6,493
Unpaid principal balance	7,386	7,386	7,262
Average balance	6,500	6,497	6,776
Consumer and Other | Other Consumer
Summary of the impaired loans by portfolio class of loans
Loans with a specific valuation allowance, Recorded balance	1,156	1,156	1,851
Loans with a specific valuation allowance, Unpaid principal balance	1,192	1,192	1,934
Specific valuation allowance	394	394	372
Loans with a specific valuation allowance, Average balance	1,302	1,485	1,762
Loans without a specific valuation allowance, Recorded balance	2,085	2,085	1,943
Loans without a specific valuation allowance, Unpaid principal balance	2,170	2,170	2,029
Loans without a specific valuation allowance, Average balance	2,088	2,040	2,228
Recorded balance	3,241	3,241	3,794
Unpaid principal balance	3,362	3,362	3,963
Average balance	$ 3,390	$ 3,525	$ 3,990