Accumulated Other Comprehensive Income, Reclassified (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Amortization of pension and postretirement benefit plans [Abstract]
Prior service benefit		$ (54)	$ (112)	$ (3,017)
Unrecognized loss		763	2,261	2,435
Income tax (expense) benefit		(514)	(1,325)	$ 372
Total reclassifications for the period		408	1,269
Reclassification out of Accumulated Other Comprehensive Income [Member]
Amortization of pension and postretirement benefit plans [Abstract]
Prior service benefit	[1]	(54)	(112)
Unrecognized loss	[1]	763	2,261
Total before income tax		709	2,149
Income tax (expense) benefit		(301)	(880)
Total reclassifications for the period		$ 408	$ 1,269

[1] These accumulated other comprehensive income components are included in the computation of net periodic pension and postretirement benefit costs, which are included in selling, general and administrative expenses in our consolidated statements of operations (see Notes 13 and 14 for additional details).