Income Taxes (Details) - The income tax effects of temporary differences that comprise deferred tax assets and liabilities - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Noncurrent deferred tax assets (liabilities):
Accounts receivable	$ 150	$ 294
Other accrued expenses	248	425
Property, plant and equipment	(1,255)	(1,187)
Employee benefits	4,252	5,649
Contribution carryforward	278	279
AMT credit	676	631
Net operating loss	14,845	15,633
Gross non-current deferred tax assets (liabilities)	19,194	21,724
Less valuation allowance	$ (19,194)	$ (21,724)
Net noncurrent deferred tax assets (liabilities)