Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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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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Amount of expense related to estimated loss from loan and lease transactions.

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Allowance for Loan Losses - Activity by Class (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				$ 10,138				$ 9,916	$ 10,138	$ 9,916	$ 10,344
Chargeoffs									1,618	1,721	2,373
Recoveries									209	343	395
Provision for loan losses	$ 250	$ 750	$ 500	500	$ 475	$ 375	$ 375	375	2,000	1,600	1,550
Ending balance	10,729				10,138				10,729	10,138	9,916
Ending balance specifically evaluated for impairment	1,812				974				1,812	974	754
Ending balance collectively evaluated for impairment	8,917				9,164				8,917	9,164	9,162
Loans	1,164,139				1,071,526				1,164,139	1,071,526	988,638
Ending balance specifically evaluated for impairment	31,392				27,583				31,392	27,583	29,531
Ending balance collectively evaluated for impairment	1,132,747				1,043,943				1,132,747	1,043,943	959,107
Commercial \| Real Estate
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				3,988				3,120	3,988	3,120	3,532
Chargeoffs									587	294	280
Recoveries									0	0	2
Provision for loan losses									471	1,162	(134)
Ending balance	3,872				3,988				3,872	3,988	3,120
Ending balance specifically evaluated for impairment	224				505				224	505	89
Ending balance collectively evaluated for impairment	3,648				3,483				3,648	3,483	3,031
Loans	323,809				302,506				323,809	302,506	269,462
Ending balance specifically evaluated for impairment	7,790				10,021				7,790	10,021	10,717
Ending balance collectively evaluated for impairment	316,019				292,485				316,019	292,485	258,745
Commercial \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				396				580	396	580	823
Chargeoffs									0	75	9
Recoveries									0	8	1
Provision for loan losses									38	(117)	(235)
Ending balance	434				396				434	396	580
Ending balance specifically evaluated for impairment	0				100				0	100	302
Ending balance collectively evaluated for impairment	434				296				434	296	278
Loans	38,056				25,406				38,056	25,406	24,881
Ending balance specifically evaluated for impairment	741				763				741	763	1,026
Ending balance collectively evaluated for impairment	37,315				24,643				37,315	24,643	23,855
Commercial \| Other
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				1,780				1,452	1,780	1,452	1,505
Chargeoffs									212	376	732
Recoveries									49	129	88
Provision for loan losses									1,741	575	591
Ending balance	3,358				1,780				3,358	1,780	1,452
Ending balance specifically evaluated for impairment	1,309				39				1,309	39	8
Ending balance collectively evaluated for impairment	2,049				1,741				2,049	1,741	1,444
Loans	181,528				150,769				181,528	150,769	128,341
Ending balance specifically evaluated for impairment	9,918				1,743				9,918	1,743	1,234
Ending balance collectively evaluated for impairment	171,610				149,026				171,610	149,026	127,107
Municipal
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				18				17	18	17	15
Chargeoffs									0	0	0
Recoveries									0	0	0
Provision for loan losses									2	1	2
Ending balance	20				18				20	18	17
Ending balance specifically evaluated for impairment	0				0				0	0	0
Ending balance collectively evaluated for impairment	20				18				20	18	17
Loans	33,391				27,056				33,391	27,056	19,751
Ending balance specifically evaluated for impairment	0				0				0	0	0
Ending balance collectively evaluated for impairment	33,391				27,056				33,391	27,056	19,751
Residential \| Construction
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				44				24	44	24	20
Chargeoffs									0	0	0
Recoveries									0	0	0
Provision for loan losses									(8)	20	4
Ending balance	36				44				36	44	24
Ending balance specifically evaluated for impairment	0				0				0	0	0
Ending balance collectively evaluated for impairment	36				44				36	44	24
Loans	17,868				18,303				17,868	18,303	8,451
Ending balance specifically evaluated for impairment	0				0				0	0	0
Ending balance collectively evaluated for impairment	17,868				18,303				17,868	18,303	8,451
Residential \| Term
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				1,288				1,391	1,288	1,391	1,185
Chargeoffs									456	379	420
Recoveries									40	93	152
Provision for loan losses									258	183	474
Ending balance	1,130				1,288				1,130	1,288	1,391
Ending balance specifically evaluated for impairment	255				304				255	304	326
Ending balance collectively evaluated for impairment	875				984				875	984	1,065
Loans	432,661				411,469				432,661	411,469	403,030
Ending balance specifically evaluated for impairment	11,748				13,669				11,748	13,669	15,088
Ending balance collectively evaluated for impairment	420,913				397,800				420,913	397,800	387,942
Home Equity LIne of Credit
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				807				893	807	893	1,060
Chargeoffs									28	147	582
Recoveries									11	5	31
Provision for loan losses									(98)	56	384
Ending balance	692				807				692	807	893
Ending balance specifically evaluated for impairment	24				26				24	26	29
Ending balance collectively evaluated for impairment	668				781				668	781	864
Loans	111,302				110,907				111,302	110,907	110,202
Ending balance specifically evaluated for impairment	1,179				1,387				1,179	1,387	1,466
Ending balance collectively evaluated for impairment	110,123				109,520				110,123	109,520	108,736
Consumer
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				559				566	559	566	542
Chargeoffs									335	450	350
Recoveries									109	108	121
Provision for loan losses									212	335	253
Ending balance	545				559				545	559	566
Ending balance specifically evaluated for impairment	0				0				0	0	0
Ending balance collectively evaluated for impairment	545				559				545	559	566
Loans	25,524				25,110				25,524	25,110	24,520
Ending balance specifically evaluated for impairment	16				0				16	0	0
Ending balance collectively evaluated for impairment	25,508				25,110				25,508	25,110	24,520
Unallocated
Allowance for Loan and Lease Losses [Roll Forward]
Beginning balance				$ 1,258				$ 1,873	1,258	1,873	1,662
Chargeoffs									0	0	0
Recoveries									0	0	0
Provision for loan losses									(616)	(615)	211
Ending balance	642				1,258				642	1,258	1,873
Ending balance specifically evaluated for impairment	0				0				0	0	0
Ending balance collectively evaluated for impairment	642				1,258				642	1,258	1,873
Loans	0				0				0	0	0
Ending balance specifically evaluated for impairment	0				0				0	0	0
Ending balance collectively evaluated for impairment	$ 0				$ 0				$ 0	$ 0	$ 0