Loans - Aging of Past Due Loans by Class of Loans - Tabular Disclosure (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Aging of Past Due Loans by Class of Loans
Total Past Due	$ 6,898	$ 7,989
Loans Not Past Due	1,559,953	1,495,378
Total loan balance	1,566,851	1,503,367
30-59 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	3,798	4,630
60-89 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	1,432	1,124
90 Days or Greater Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	1,668	2,235
Commercial
Aging of Past Due Loans by Class of Loans
Total Past Due	4,974	6,891
Loans Not Past Due	582,302	597,440
Total loan balance	587,276	604,331
Commercial \| 30-59 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	3,798	3,998
Commercial \| 60-89 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	601	857
Commercial \| 90 Days or Greater Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	575	2,036
Real estate
Aging of Past Due Loans by Class of Loans
Total loan balance	967,826	878,576
Consumer
Aging of Past Due Loans by Class of Loans
Loans Not Past Due	11,749	20,460
Total loan balance	11,749	20,460
Commercial \| Real estate
Aging of Past Due Loans by Class of Loans
Total Past Due		632
Loans Not Past Due		661,596
Total loan balance	754,856	662,228
Commercial \| Real estate \| 30-59 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due		632
CRE \| Real estate
Aging of Past Due Loans by Class of Loans
Total Past Due	831
Loans Not Past Due	754,025
Total loan balance	754,856	662,228
CRE \| Real estate \| 60-89 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	831
Land and construction \| Real estate
Aging of Past Due Loans by Class of Loans
Total Past Due	1,093	199
Loans Not Past Due	91,217	80,803
Total loan balance	92,310	81,002
Land and construction \| Real estate \| 90 Days or Greater Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	1,093	199
Home equity \| Real estate
Aging of Past Due Loans by Class of Loans
Total Past Due		267
Loans Not Past Due	74,171	82,192
Total loan balance	74,171	82,459
Home equity \| Real estate \| 60-89 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due		267
Residential mortgages \| Real estate
Aging of Past Due Loans by Class of Loans
Loans Not Past Due	46,489	52,887
Total loan balance	$ 46,489	$ 52,887

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Financing receivables that are current.

+ References

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Recorded Investment in financing receivables that are past due at the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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