Condensed Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2015	Mar. 31, 2015	Sep. 30, 2014	Jun. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Schedule of Equity Method Investments [Line Items]
Equity Method Investment	$ 19,617				$ 19,617		$ 21,751
Revenue Recognized Under Net Reporting Arrangements	12,140		$ 11,829		36,193	$ 33,328
Kelko (Venezuela) [Member]
Schedule of Equity Method Investments [Line Items]
Effect Of Currency Conversion, Amount		$ 2,806		$ 321
Effect Of Currency Conversion, Per Diluted Share		$ 0.21		$ 0.02
Equity Method Investment	$ 174				$ 174