Income Taxes - Significant components of the Company’s deferred taxes (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Deferred income tax liabilities
Property, plant and equipment	$ 18,297	$ 24,748
Tax-deductible goodwill	7,437	5,206
Non-deductible intangibles	4,135	5,069
State deferred taxes	1,148	1,487
Other	484	392
Deferred tax liabilities, gross	31,501	36,902
Deferred income tax assets
Compensation	6,104	6,243
Inventory valuation	765	806
Allowance for uncollectible accounts	1,007	967
Non-deductible accruals	2,116	3,820
Other	0	78
Net operating loss carryforwards	4,612	4,975
Deferred tax assets, gross	14,604	16,889
Deferred Tax Assets, Valuation Allowance	(5,221)	(6,060)
Deferred Tax Assets, Net of Valuation Allowance	9,383	10,829
Deferred Tax Liabilities, Net	$ 22,118	$ 26,073