CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Statement Of Income and Comprehensive Income [Abstract]
Net Income	$ 1,317	$ 1,753
Other comprehensive loss:
Retirement benefits adjustment, net of income taxes	(12)	(17)
Total comprehensive income	$ 1,305	$ 1,736