Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net income (loss)	$ (4,263)	$ (4,172)	$ (9,866)	$ (2,558)
Other comprehensive income (loss):
Adjustment to pension liability	596	1,557	1,466	2,902
Tax expense	(239)	(623)	(586)	(1,161)
Adjustment to pension liability, net of tax	357	934	880	1,741
Foreign currency translation adjustment	(949)	1,386	(1,419)	(101)
Total other comprehensive income (loss), net of tax	(592)	2,320	(539)	1,640
Comprehensive loss	(4,855)	(1,852)	(10,405)	(918)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance			140,316	326,676
Other comprehensive income (loss), net of tax, before reclassifications			(1,419)	(101)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			880	1,741
Total other comprehensive income (loss), net of tax	(592)	2,320	(539)	1,640
Balance	125,118	313,780	125,118	313,780
Defined Benefit Pension Items
Other comprehensive income (loss):
Total other comprehensive income (loss), net of tax			880	1,741
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance			(43,915)	(49,560)
Other comprehensive income (loss), net of tax, before reclassifications			0	0
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			880	1,741
Total other comprehensive income (loss), net of tax			880	1,741
Balance	(43,035)	(47,819)	(43,035)	(47,819)
Foreign Currency Items
Other comprehensive income (loss):
Total other comprehensive income (loss), net of tax			(1,419)	(101)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance			355	2,331
Other comprehensive income (loss), net of tax, before reclassifications			(1,419)	(101)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax			0	0
Total other comprehensive income (loss), net of tax			(1,419)	(101)
Balance	(1,064)	2,230	(1,064)	2,230
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance			(43,560)	(47,229)
Balance	$ (44,099)	$ (45,589)	$ (44,099)	$ (45,589)