Stock-Based Compensation (Summary Of SAR Activity) (Details) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2016 USD ($) $ / shares shares
Stock Appreciation Rights [Roll Forward]
Outstanding, Shares, Beginning Balance | shares	1,588,457
Granted, Shares | shares	251,982
Forfeited, Shares | shares	(13,916)
Expired, Shares | shares	(1,375)
Exercised, Shares | shares	(469,903)
Outstanding, Shares, Ending Balance | shares	1,355,245
Outstanding, Weighted Average Exercise Price, Beginning Balance | $ / shares	$ 33.74
Granted, Weighted Average Exercise Price | $ / shares	41.35
Forfeited, Weighted Average Exercise Price | $ / shares	38.06
Expired, Weighted Average Exercise Price | $ / shares	37.19
Exercised, Weighted Average Exercise Price | $ / shares	31.37
Outstanding, Weighted Average Exercise Price, Ending Balance | $ / shares	$ 35.93
Outstanding, Weighted Average Remaining Contractual Term (in years)	5 years 7 months
Outstanding, Aggregate Intrinsic Value, Ending Balance | $	$ 18,068