Income Taxes - Significant Components of the Company's Deferred Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred income tax liabilities
Property, plant and equipment	$ 12,989	$ 11,629
Tax-deductible goodwill	7,871	7,728
Non-deductible intangibles	282	1,843
State deferred taxes	212	687
Other	1,010	483
Deferred tax liabilities, gross	22,364	22,370
Deferred income tax assets
Compensation	7,081	6,716
Inventory valuation	945	636
Allowance for uncollectible accounts	194	260
Non-deductible accruals	3,892	2,631
Other	0	15
Net operating loss carryforwards	4,715	5,050
Deferred tax assets, gross	16,827	15,308
Valuation Allowance	(3,664)	(4,326)
Deferred Tax Assets, Net of Valuation Allowance	13,163	10,982
Net deferred income tax liability	$ 9,201	$ 11,388