Stock Compensation (Schedule Of Stock Grant Activity For PSUs) (Details) - Performance Stock Units (PSUs) [Member] - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested, Beginning Balance, Shares	147,000	169,000	188,000
Granted, Shares	322,000	104,000	126,000
Vested, Shares	(87,000)	(109,000)	(128,000)
Forfeited, Shares	(35,000)	(17,000)	(17,000)
Unvested, Ending Balance, Shares	347,000	147,000	169,000	188,000
Vested and expected to vest, Shares	347,000
Outstanding, Weighted Average Remaining Contractual Term in Years	2 years 3 months 29 days	8 months 19 days	8 months 15 days	9 months 7 days
Vested and expected to vest, Weighted Average Remaining Contractual Term in Years	2 years 3 months 29 days
Outstanding, Aggregate Intrinsic Value	$ 9,400,000	$ 4,179,000	$ 3,236,000	$ 3,603,000
Vested and expected to vest, Aggregate Intrinsic Value	$ 9,400,000