Summary of Significant Accounting Policies (Details) $ in Thousands	6 Months Ended		12 Months Ended
	Jun. 30, 2018 USD ($) Office shares	Dec. 31, 2017	Jun. 30, 2018 USD ($) Office shares	Jun. 30, 2017 USD ($) shares
Nature of Operations [Abstract]
Number of offices | Office	14		14
Cash and Cash Equivalents [Abstract]
Interest-bearing deposits in banks and other financial institutions | $	$ 16,700		$ 16,700	$ 6,100
Income Recognition on Impaired and Nonaccrual loans [Abstract]
Threshold period of delinquency after which a loan is placed on nonaccrual status			90 days
Treasury Stock [Abstract]
Total number of shares repurchased under the plan (in shares) | shares	124,956		124,956
Stock Repurchased During Period, Shares | shares			0	0
Federal Home Loan Bank Stock [Abstract]
Other-than-temporary impairment charge | $			$ 0	$ 0
Advertising [Abstract]
Advertising expense | $			$ 354	$ 387
Impact of Recent Accounting Pronouncements [Abstract]
Federal corporate tax rate	21.00%		28.10%	34.00%
Maximum [Member]
Treasury Stock [Abstract]
Number of shares authorized for repurchase (in shares) | shares	184,692		184,692
Impact of Recent Accounting Pronouncements [Abstract]
Federal corporate tax rate		35.00%
Building and Improvements [Member]
Premises and Equipment [Abstract]
Property, plant and equipment, useful life			39 years
Furniture and Equipment [Member] | Minimum [Member]
Premises and Equipment [Abstract]
Property, plant and equipment, useful life			3 years
Furniture and Equipment [Member] | Maximum [Member]
Premises and Equipment [Abstract]
Property, plant and equipment, useful life			8 years