Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred tax assets:
Allowance for doubtful accounts	$ 28	$ 65
Inventory valuation	279	607
Accrued expense	927	372
Unrealized foreign exchange loss	652	634
Net operating loss carryforward	1,999	2,148
Goodwill		2,159
Deferred financing costs	1,564
Asset retirement obligation	179	292
Stock compensation	322	1,853
Total gross deferred tax asset	5,950	8,130
Valuation allowance	(3,717)	(4,120)
Net deferred tax assets	2,233	4,010
Deferred tax liabilities:
Plant, property and leasehold improvements	(5,881)	(4,238)
Intangibles	(18,962)	(11,903)
Prepaid expense	(1,463)	(1,045)
Total gross deferred tax liabilities	(26,306)	(17,186)
Net deferred tax liabilities	$ (24,073)	$ (13,176)