Loans - Aging of Past Due Loans by Class of Loans - Tabular Disclosure (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Aging of Past Due Loans by Class of Loans
Total Past Due	$ 6,095	$ 7,989
Loans Not Past Due	1,508,084	1,495,378
Total loan balance	1,514,179	1,503,367
30-59 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	3,441	4,630
60-89 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	506	1,124
90 Days or Greater Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	2,148	2,235
Commercial
Aging of Past Due Loans by Class of Loans
Total Past Due	5,391	6,891
Loans Not Past Due	603,962	597,440
Total loan balance	609,353	604,331
Commercial \| 30-59 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	2,932	3,998
Commercial \| 60-89 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	506	857
Commercial \| 90 Days or Greater Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	1,953	2,036
Real estate
Aging of Past Due Loans by Class of Loans
Total loan balance	891,019	878,576
Consumer
Aging of Past Due Loans by Class of Loans
Loans Not Past Due	13,807	20,460
Total loan balance	13,807	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	679,989	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	509
Loans Not Past Due	679,480
Total loan balance	679,989	662,228
CRE \| Real estate \| 30-59 Days Past Due
Aging of Past Due Loans by Class of Loans
Total Past Due	509
Land and construction \| Real estate
Aging of Past Due Loans by Class of Loans
Total Past Due	195	199
Loans Not Past Due	80,906	80,803
Total loan balance	81,101	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	195	199
Home equity \| Real estate
Aging of Past Due Loans by Class of Loans
Total Past Due		267
Loans Not Past Due	80,360	82,192
Total loan balance	80,360	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	49,569	52,887
Total loan balance	$ 49,569	$ 52,887

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Financing receivables that are current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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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
-Name Accounting Standards Codification
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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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