Loans and Allowance for Loan Losses - Impaired Financing Receivables (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Financing Receivable, Impaired [Line Items]
Recorded Investment with specific reserves	$ 294	$ 1,671
Unpaid Principal Balance with specific reserves	294	1,699
Interest Income Recognized with specific reserves	15	5
Specific Reserve with specific reserves	226	782
Recorded Investment	347	1,740
Recorded Investment with no specific reserve	2,435	2,643
Unpaid Principal Balance with no specific reserve	3,569	3,411
Interest Income Recognized with no specific reserve	45	50
Specific Reserve	200	800
Average Recorded Investment with no specific reserve	3,179	3,528
Consumer
Financing Receivable, Impaired [Line Items]
Recorded Investment with specific reserves	89	160
Unpaid Principal Balance with specific reserves	89	160
Interest Income Recognized with specific reserves	3	5
Specific Reserve with specific reserves	22	52
Recorded Investment	136	205
Recorded Investment with no specific reserve	116	88
Unpaid Principal Balance with no specific reserve	457	88
Residential real estate
Financing Receivable, Impaired [Line Items]
Recorded Investment with specific reserves		1,294
Unpaid Principal Balance with specific reserves		1,322
Specific Reserve with specific reserves		513
Recorded Investment		1,312
Recorded Investment with no specific reserve	96	49
Unpaid Principal Balance with no specific reserve	300	49
Interest Income Recognized with no specific reserve	2
Average Recorded Investment with no specific reserve	50
Commercial
Financing Receivable, Impaired [Line Items]
Specific Reserve with specific reserves	204	217
Recorded Investment with no specific reserve	1,267	1,194
Unpaid Principal Balance with no specific reserve	1,267	1,194
Interest Income Recognized with no specific reserve	39	39
Average Recorded Investment with no specific reserve	1,148	1,632
Home Equity Portfolio Segment
Financing Receivable, Impaired [Line Items]
Recorded Investment with no specific reserve		318
Unpaid Principal Balance with no specific reserve		318
Average Recorded Investment with no specific reserve		322
Residential Real estate
Financing Receivable, Impaired [Line Items]
Specific Reserve with specific reserves		513
Installment
Financing Receivable, Impaired [Line Items]
Recorded Investment with no specific reserve		2
Unpaid Principal Balance with no specific reserve		2
Average Recorded Investment with no specific reserve		2
Commercial Mortgage Portfolio Segment
Financing Receivable, Impaired [Line Items]
Recorded Investment with specific reserves	204	217
Unpaid Principal Balance with specific reserves	204	217
Interest Income Recognized with specific reserves	12
Specific Reserve with specific reserves	204	217
Recorded Investment	211	223
Recorded Investment with no specific reserve	956	992
Unpaid Principal Balance with no specific reserve	1,545	1,760
Interest Income Recognized with no specific reserve	4	11
Average Recorded Investment with no specific reserve	$ 1,981	$ 1,572

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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