Employee Benefits (Multiemployer Plans) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014 plan
Defined Benefit Pension Plans and Defined Benefit Postretirement Plans Disclosure [Abstract]
Number of multiemployer plans	2
Contributions to multi-employer plans	$ 2,295	[1]

[1] The plan information for both the Pensionskasse der Mitarbeiter der Hoechst-Gruppe VVaG and Pensionskasse der Wacker-Chemie GmbH VVaG plans is publicly available. The plans provide fixed, monthly retirement payments on the basis of the credits earned by the participating employees. To the extent that the plans are underfunded, future contributions to the plans may increase and may be used to fund retirement benefits for employees related to other employers. The Company does not consider either of its multi-employer plans individually significant.