CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net income	$ 29,300	$ 34,681	$ 29,516
Other comprehensive income (loss); change in funded status of pension plan, net of $7, $1,016 and $2,654 in tax for 2016, 2015 and 2014, respectively	(32)	(1,599)	(3,956)
Comprehensive income	$ 29,268	$ 33,082	$ 25,560