Stockholders' Equity AOCI Change (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax		$ 0	$ 0
Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, Net of Tax	[1]	(214)	(456)
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax		214	456
Accumulated Other Comprehensive Loss, Pension and Other Postretirement Benefit Plans, Net of Tax		(9,583)	(16,729)	$ (9,797)	$ (17,185)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax		(1,000)	611
Other Comprehensive Income (loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Net of Tax	[1]	0	0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax		(1,000)	611
Accumulated Other Comprehensive Loss, Foreign Currency Translation Adjustment, Net of Tax		(17,142)	(16,025)	$ (16,142)	$ (16,636)
Beginning Balance		(25,939)	(33,821)
Other comprehensive (loss) income before reclassifications		(1,000)	611
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	[1]	214	456
Net current period other comprehensive income (loss)		(786)	1,067
Ending Balance		(26,725)	$ (32,754)
AOCI Attributable to Parent [Member]
Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, Net of Tax		214
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax		$ (1,000)

[1] See reclassifications from accumulated other comprehensive loss table below for details of reclassification from accumulated other comprehensive loss for the three month periods ended March 31, 2017 and 2016.