Fair Value Measurements, Estimated Fair Values and Related Carrying or Notional Amounts (Details) - USD ($) $ in Thousands		Mar. 31, 2018	Dec. 31, 2017
Assets [Abstract]
Cash and cash equivalents		$ 43,437	$ 14,412
Securities available-for-sale		145,857	157,121
Restricted securities		4,023	3,846
Loans held for sale		715	779
Loans, net of allowances for loan losses	[1]	723,144	729,092
Bank owned life insurance		26,190	25,981
Accrued interest receivable		2,787	3,254
Liabilities [Abstract]
Deposits		789,027	783,594
Federal funds purchased			10,000
Overnight repurchase agreements		36,141	20,693
Federal Home Loan Bank advances		70,000	67,500
Accrued interest payable		364	360
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Assets [Abstract]
Cash and cash equivalents		43,437	14,412
Securities available-for-sale		0	0
Restricted securities		0	0
Loans held for sale		0	0
Loans, net of allowances for loan losses	[1]	0	0
Bank owned life insurance		0	0
Accrued interest receivable		0	0
Liabilities [Abstract]
Deposits		0	0
Federal funds purchased			0
Overnight repurchase agreements		0	0
Federal Home Loan Bank advances		0	0
Accrued interest payable		0	0
Significant Other Observable Inputs (Level 2) [Member]
Assets [Abstract]
Cash and cash equivalents		0	0
Securities available-for-sale		145,857	157,121
Restricted securities		4,023	3,846
Loans held for sale		715	779
Loans, net of allowances for loan losses	[1]	0	0
Bank owned life insurance		26,190	25,981
Accrued interest receivable		2,787	3,254
Liabilities [Abstract]
Deposits		790,246	782,539
Federal funds purchased			10,000
Overnight repurchase agreements		36,141	20,693
Federal Home Loan Bank advances		69,716	67,329
Accrued interest payable		364	360
Significant Unobservable Inputs (Level 3) [Member]
Assets [Abstract]
Cash and cash equivalents		0	0
Securities available-for-sale		0	0
Restricted securities		0	0
Loans held for sale		0	0
Loans, net of allowances for loan losses	[1]	705,413	722,464
Bank owned life insurance		0	0
Accrued interest receivable		0	0
Liabilities [Abstract]
Deposits		0	0
Federal funds purchased			0
Overnight repurchase agreements		0	0
Federal Home Loan Bank advances		0	0
Accrued interest payable		$ 0	$ 0

[1] In accordance with the adoption of ASU 2016-01, the fair values of loans held for investment and time deposits as of March 31, 2018 were measured using an exit price notion. The fair values of loans held for investment and time deposits as of December 31, 2017 were measured using an entry price notion.