Share-Based Employee Compensation - Share-Based Compensation Including Expense for Phantom Stock Units and Cash Settled Stock Appreciation Rights Granted to Employees (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Cost of employee share-based compensation included in income, before income tax	$ (491)	$ 1,888	$ 2,590	$ 4,257
Cost of sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Cost of employee share-based compensation included in income, before income tax	(55)	84	71	229
Operating expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Cost of employee share-based compensation included in income, before income tax	$ (436)	$ 1,804	$ 2,519	$ 4,028