Stock-Based And Long-Term Incentive Compensation (Summary Of Compensation Expense and Tax Benefits) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Compensation expense	$ 19,692	$ 30,987	$ 35,928
Related income taxes	4,569	7,189	8,335
Total compensation expense, net of income taxes	15,123	23,798	27,593
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Compensation expense	2,743	4,247	4,289
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Compensation expense	15,716	19,828	21,899
Cash Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Compensation expense	298
Performance Share Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Compensation expense	$ 935	$ 6,912	$ 9,740