CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Statement of Comprehensive Income [Abstract]
Net income	$ 4,107	$ 10,447
Other comprehensive (loss), net of tax:
Net actuarial pension loss amortization, net of income tax of $0 and $0	0	1
Prior service cost (credit) amortization, net of income tax of $149 and $150	(239)	(239)
Other comprehensive (loss), net of tax	(239)	(238)
Comprehensive income	$ 3,868	$ 10,209