CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Statement Of Income and Comprehensive Income [Abstract]
Net income	$ 1,753	$ 4,597
Other comprehensive (loss) income:
Retirement benefits adjustment, net of income taxes	(17)	11
Total comprehensive income	$ 1,736	$ 4,608