Stock-Based Employee Compensation (Expense Recognized) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs
Employee stock-base compensation expense	$ 69,459	$ 32,659	$ 36,073
Marketing, selling and administrative expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs
Employee stock-base compensation expense	$ 69,459	$ 32,659	$ 36,073