(Summary Of Outstanding And Exercisable Stock Options) (Details) - $ / shares shares in Thousands	12 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	3,278	4,920
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	5 years 6 months 41 days
Options Outstanding, Weighted-Average Exercise Prices	$ 35.09	$ 37.44
Options exercisable, number of shares	2,206
Options exercisable, weighted-average exercise prices	$ 36.55
Eleven Point Five Three To Twenty Three Point Eight Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	317
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	3 years 3 months 50 days
Options Outstanding, Weighted-Average Exercise Prices	$ 19.10
Options Outstanding, Potential Dilution	0.10%
Options exercisable, number of shares	313
Options exercisable, weighted-average exercise prices	$ 19.18
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	1,000
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	7 years 6 months 30 days
Options Outstanding, Weighted-Average Exercise Prices	$ 26.25
Options Outstanding, Potential Dilution	0.30%
Options exercisable, number of shares	580
Options exercisable, weighted-average exercise prices	$ 26.25
Options Exercisable, Potential Dilution	0.20%
Twenty Seven Point Four Nine 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	853
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	8 years 2 months 15 days
Options Outstanding, Weighted-Average Exercise Prices	$ 35.50
Options Outstanding, Potential Dilution	0.30%
Options exercisable, number of shares	343
Options exercisable, weighted-average exercise prices	$ 35.21
Options Exercisable, Potential Dilution	0.10%
Thirty Six To Fifty Nine Point Six Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	1,108
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	2 years 4 months 50 days
Options Outstanding, Weighted-Average Exercise Prices	$ 47.33
Options Outstanding, Potential Dilution	0.40%
Options exercisable, number of shares	970
Options exercisable, weighted-average exercise prices	$ 48.78
Options Exercisable, Potential Dilution	0.30%
Eleven Point Five Three To Fifty Nine Point Six Three [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, number of shares	3,278
Options Outstanding, Weighted-Average Remaining Contractual Term (in years)	5 years 6 months 40 days
Options Outstanding, Weighted-Average Exercise Prices	$ 35.09
Options Outstanding, Potential Dilution	1.10%
Options exercisable, number of shares	2,206
Options exercisable, weighted-average exercise prices	$ 36.55
Options Exercisable, Potential Dilution	0.70%