(Summary Of Outstanding And Exercisable Stock Options) (Details) - $ / shares shares in Thousands	12 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	1,615	2,377
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	5 years 5 months 10 days
Options Outstanding, Weighted-Average Exercise Prices	$ 30.28	$ 33.35
Options exercisable, number of shares	1,615
Options exercisable, weighted-average exercise prices	$ 30.28
Eleven Point Five Three To Three Point Six One [Member] [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	119
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	1 year 4 months 28 days
Options Outstanding, Weighted-Average Exercise Prices	$ 19.80
Options Outstanding, Potential Dilution	0.00%
Options exercisable, number of shares	119
Options exercisable, weighted-average exercise prices	$ 19.80
Options Exercisable, Potential Dilution	0.10%
Twenty Six Point Two Five To Twenty Six Point Two Five [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	750
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	5 years 6 months 32 days
Options Outstanding, Weighted-Average Exercise Prices	$ 26.25
Options Outstanding, Potential Dilution	0.30%
Options exercisable, number of shares	750
Options exercisable, weighted-average exercise prices	$ 26.25
Options Exercisable, Potential Dilution	0.20%
Thirty Three Point Six Zero To Thirty Five Point Seven Zero [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	746
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	5 years 10 months 38 days
Options Outstanding, Weighted-Average Exercise Prices	$ 36.01
Options Outstanding, Potential Dilution	0.20%
Options exercisable, number of shares	746
Options exercisable, weighted-average exercise prices	$ 36.01
Options Exercisable, Potential Dilution	0.20%
Eleven Point Five Three To Fifty Eight Point One Four [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	1,615
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	5 years 5 months 10 days
Options Outstanding, Weighted-Average Exercise Prices	$ 30.28
Options Outstanding, Potential Dilution	0.50%
Options exercisable, number of shares	1,615
Options exercisable, weighted-average exercise prices	$ 30.28
Options Exercisable, Potential Dilution	0.50%