(Summary Of Outstanding And Exercisable Stock Options) (Details) - $ / shares shares in Thousands	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	2,377	3,278
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	5 years 3 months 18 days
Options Outstanding, Weighted-Average Exercise Prices	$ 33.35	$ 35.09
Options exercisable, number of shares	1,903
Options exercisable, weighted-average exercise prices	$ 33.61
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	178
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	2 years 5 months 24 days
Options Outstanding, Weighted-Average Exercise Prices	$ 19.40
Options Outstanding, Potential Dilution	0.10%
Options exercisable, number of shares	178
Options exercisable, weighted-average exercise prices	$ 19.40
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	950
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	6 years 6 months 28 days
Options Outstanding, Weighted-Average Exercise Prices	$ 26.25
Options Outstanding, Potential Dilution	0.30%
Options exercisable, number of shares	770
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	597
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	7 years 2 months 19 days
Options Outstanding, Weighted-Average Exercise Prices	$ 35.45
Options Outstanding, Potential Dilution	0.20%
Options exercisable, number of shares	372
Options exercisable, weighted-average exercise prices	$ 35.30
Options Exercisable, Potential Dilution	0.10%
Thirty Six Point Zero 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	652
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	2 years 5 months 10 days
Options Outstanding, Weighted-Average Exercise Prices	$ 45.59
Options Outstanding, Potential Dilution	0.20%
Options exercisable, number of shares	583
Options exercisable, weighted-average exercise prices	$ 46.59
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	2,377
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	5 years 3 months 18 days
Options Outstanding, Weighted-Average Exercise Prices	$ 33.35
Options Outstanding, Potential Dilution	0.80%
Options exercisable, number of shares	1,903
Options exercisable, weighted-average exercise prices	$ 33.61
Options Exercisable, Potential Dilution	0.60%