Stock-Based Compensation (Activity Of Options Outstanding Not Yet Vested) (Details) - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock-Based Compensation [Abstract]
Number of Shares, Unvested as of December 31, 2015	2,445
Number of Shares, Granted	1,357	1,076	1,121
Number of Shares, Vesting during period	(897)
Number of Shares, Forfeited or canceled	(91)
Number of Shares, Unvested as of December 31, 2016	2,814	2,445
Weighted-Average Fair Value Per Share, Unvested as of December 31, 2015	$ 21.43
Weighted-Average Fair Value Per Share, Granted	19.19	$ 24.75	$ 19.49
Weighted-Average Fair Value Per Share, Vesting during period	20.64
Weighted-Average Fair Value Per Share, Forfeited or canceled	20.82
Weighted-Average Fair Value Per Share, Unvested as of December 31, 2016	$ 20.62	$ 21.43