Fair Value - Assets Measured at Fair Value on a Recurring Basis (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	$ 99,886	$ 99,350
Equity securities	474	1,817
U.S. Treasury and federal agency
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	4,411	4,472
U.S. government sponsored entities and agencies
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	20,590	13,926
U.S. agency mortgage-backed securities: residential
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	22,544	20,758
U.S. agency collateralized mortgage obligations: residential
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	20,254	21,924
State and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	24,660	29,240
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	7,427	9,030
Level 1
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	4,411	4,472
Equity securities	474	1,683
Level 1 | U.S. Treasury and federal agency
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	4,411	4,472
Level 1 | U.S. government sponsored entities and agencies
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 1 | U.S. agency mortgage-backed securities: residential
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 1 | U.S. agency collateralized mortgage obligations: residential
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 1 | State and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 1 | Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 2
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	91,975	86,880
Equity securities	0	0
Level 2 | U.S. Treasury and federal agency
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 2 | U.S. government sponsored entities and agencies
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	20,590	13,926
Level 2 | U.S. agency mortgage-backed securities: residential
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	22,544	20,758
Level 2 | U.S. agency collateralized mortgage obligations: residential
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	20,254	21,924
Level 2 | State and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	24,660	29,240
Level 2 | Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	3,927	1,032
Level 3
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	3,500	7,998
Equity securities	0	134
Level 3 | U.S. Treasury and federal agency
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 3 | U.S. government sponsored entities and agencies
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 3 | U.S. agency mortgage-backed securities: residential
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 3 | U.S. agency collateralized mortgage obligations: residential
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 3 | State and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	0	0
Level 3 | Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Securities - available for sale	$ 3,500	$ 7,998