Stock-Based Compensation (Stock Options Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number of Shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 18,500	$ 28,300	$ 18,500
Unrecognized employee stock-based compensation	$ 6,500
Weighted average grant date fair value	$ 6.29	$ 9.25	$ 7.41
Options outstanding	3,861	6,203
Beginning balance	$ 9.76
Vesting Period	4 years
Stock-based compensation expense	$ 28,694	$ 30,584	$ 23,846
Stock Option
Number of Shares
Unrecognized employee stock-based compensation, period for recognition	1 year 10 months 20 days