Loans - Past-due Status of Loans by Class (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Schedule of Financing Receivables [Line Items]
All Past Due	$ 11,032	$ 12,658	$ 9,742
Current	1,110,054	1,058,868	1,019,250
Total	1,121,086	1,071,526	1,028,992
90 Days or More & Accruing	511	777	7
30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	1,895	2,711	1,421
60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	4,238	4,227	4,472
90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	4,899	5,720	3,849
Commercial \| Real estate
Schedule of Financing Receivables [Line Items]
All Past Due	1,971	3,476	1,486
Current	299,256	299,030	296,322
Total	301,227	302,506	297,808
90 Days or More & Accruing	0	753	0
Commercial \| Real estate \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	415	1,039	0
Commercial \| Real estate \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	169	22	385
Commercial \| Real estate \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	1,387	2,415	1,101
Commercial \| Construction
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Current	32,893	25,406	18,828
Total	32,893	25,406	18,828
90 Days or More & Accruing	0	0	0
Commercial \| Construction \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Commercial \| Construction \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Commercial \| Construction \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Commercial \| Other
Schedule of Financing Receivables [Line Items]
All Past Due	1,177	1,031	644
Current	171,809	149,738	130,554
Total	172,986	150,769	131,198
90 Days or More & Accruing	0	20	0
Commercial \| Other \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	345	202	573
Commercial \| Other \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	265	33	18
Commercial \| Other \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	567	796	53
Municipal
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Current	33,311	27,056	26,153
Total	33,311	27,056	26,153
90 Days or More & Accruing	0	0	0
Municipal \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Municipal \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Municipal \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Residential \| Construction
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Current	15,495	18,303	14,269
Total	15,495	18,303	14,269
90 Days or More & Accruing	0	0	0
Residential \| Construction \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Residential \| Construction \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Residential \| Construction \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	0	0	0
Residential \| Term
Schedule of Financing Receivables [Line Items]
All Past Due	5,904	6,403	6,235
Current	423,668	405,066	396,924
Total	429,572	411,469	403,159
90 Days or More & Accruing	344	0	0
Residential \| Term \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	295	631	414
Residential \| Term \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	3,668	3,970	3,896
Residential \| Term \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	1,941	1,802	1,925
Home equity line of credit
Schedule of Financing Receivables [Line Items]
All Past Due	1,761	1,564	1,067
Current	108,417	109,343	110,927
Total	110,178	110,907	111,994
90 Days or More & Accruing	167	0	0
Home equity line of credit \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	645	704	310
Home equity line of credit \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	130	157	49
Home equity line of credit \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	986	703	708
Consumer
Schedule of Financing Receivables [Line Items]
All Past Due	219	184	310
Current	25,205	24,926	25,273
Total	25,424	25,110	25,583
90 Days or More & Accruing	0	4	7
Consumer \| 30-59 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	195	135	124
Consumer \| 60-89 Days Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	6	45	124
Consumer \| 90 Days or More Past Due
Schedule of Financing Receivables [Line Items]
All Past Due	$ 18	$ 4	$ 62

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Recorded investment in financing receivables that are 90 days or more past due and still accruing.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Financing receivables that are current.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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