Accrued Liabilities - Components of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Accrued Liabilities
Accrued product related costs	$ 4,873	$ 5,245
Accrued income taxes	9,655	8,845
Accrued property and other taxes	1,750	1,838
Accrued outside commissions	1,294	97
Accrued professional fees	1,465	704
Accrued building improvement costs	1,709	1,768
Dividends payable	1,310	1,302
Remediation reserves	19,575	20,603
Other accrued liabilities	5,284	6,772
Total accrued liabilities	$ 46,915	$ 47,174