Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net Income (Loss)	$ 25,261	$ (74,879)	$ 19,867
Pension Adjustments:
Amortization of actuarial loss included in net income, net of tax benefit of $283, $330, and $156 for 2016, 2015, and 2014, respectively	479	557	263
Actuarial (loss) gain arising during the period, net of tax (benefit) expense of $(413), $300, and $(1,810) for 2016, 2015, and 2014, respectively	(650)	491	(3,052)
Decrease in net unrealized gains and losses on cash flow hedges, net of tax benefit of $180, $0, and $0 for 2016, 2015, and 2014, respectively	(305)	0	0
Other Comprehensive (Loss) Income, Net of Tax	(476)	1,048	(2,789)
Comprehensive Income (Loss), Net of Tax	$ 24,785	$ (73,831)	$ 17,078