Fair Value - Summary of Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Assets:
Securities available-for-sale, at fair value	$ 233,691	$ 243,808
Obligations of States and Political Subdivisions
Assets:
Securities available-for-sale, at fair value	63,400	61,926
Asset-backed securities
Assets:
Securities available-for-sale, at fair value	9,748	15,284
Other debt securities
Assets:
Securities available-for-sale, at fair value	11,809	11,734
Fair Value Measurements Recurring Basis
Assets:
Securities available-for-sale, at fair value	233,691	243,808
Liabilities:
Total derivatives	(1,506)	(1,330)
Fair Value Measurements Recurring Basis \| U.S. Government-sponsored Agencies
Assets:
Securities available-for-sale, at fair value	10,601	10,706
Fair Value Measurements Recurring Basis \| Obligations of States and Political Subdivisions
Assets:
Securities available-for-sale, at fair value	63,400	61,926
Fair Value Measurements Recurring Basis \| Mortgage-backed Securities-residential
Assets:
Securities available-for-sale, at fair value	138,133	144,158
Fair Value Measurements Recurring Basis \| Asset-backed securities
Assets:
Securities available-for-sale, at fair value	9,748	15,284
Fair Value Measurements Recurring Basis \| Other debt securities
Assets:
Securities available-for-sale, at fair value	11,809	11,734
Fair Value Measurements Recurring Basis \| Interest Rate Swaps - Customer Related
Assets:
Interest rate swaps - customer related	464	494
Liabilities:
Total derivatives	(464)	(494)
Interest rate swaps - customer related	464	494
Fair Value Measurements Recurring Basis \| Interest Rate Swaps - Cash Flow Hedges
Liabilities:
Total derivatives	(1,042)	(836)
Fair Value Measurements Recurring Basis \| Significant Other Observable Inputs (Level 2)
Assets:
Securities available-for-sale, at fair value	233,691	243,808
Liabilities:
Total derivatives	(1,506)	(1,330)
Fair Value Measurements Recurring Basis \| Significant Other Observable Inputs (Level 2) \| U.S. Government-sponsored Agencies
Assets:
Securities available-for-sale, at fair value	10,601	10,706
Fair Value Measurements Recurring Basis \| Significant Other Observable Inputs (Level 2) \| Obligations of States and Political Subdivisions
Assets:
Securities available-for-sale, at fair value	63,400	61,926
Fair Value Measurements Recurring Basis \| Significant Other Observable Inputs (Level 2) \| Mortgage-backed Securities-residential
Assets:
Securities available-for-sale, at fair value	138,133	144,158
Fair Value Measurements Recurring Basis \| Significant Other Observable Inputs (Level 2) \| Asset-backed securities
Assets:
Securities available-for-sale, at fair value	9,748	15,284
Fair Value Measurements Recurring Basis \| Significant Other Observable Inputs (Level 2) \| Other debt securities
Assets:
Securities available-for-sale, at fair value	11,809	11,734
Fair Value Measurements Recurring Basis \| Significant Other Observable Inputs (Level 2) \| Interest Rate Swaps - Customer Related
Assets:
Interest rate swaps - customer related	464	494
Liabilities:
Total derivatives	(464)	(494)
Interest rate swaps - customer related	464	494
Fair Value Measurements Recurring Basis \| Significant Other Observable Inputs (Level 2) \| Interest Rate Swaps - Cash Flow Hedges
Liabilities:
Total derivatives	$ (1,042)	$ (836)

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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