Executive Stock Plans And Stock-Based Compensation (Summary Of Stock Option And SAR Activity) (Details) shares in Thousands	12 Months Ended
	Mar. 31, 2017 $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Outstanding at beginning of year, Weighted-Average Exercise Price | $ / shares	$ 59.96
Outstanding at beginning of year, Shares | shares	152,201
Exercised, Shares | shares	(135,334)
Cancelled/expired, Shares | shares	(16,867)
Outstanding at end of year, Shares | shares	0
Exercised, Weighted-Average Exercise Price | $ / shares	$ 61.72
Cancelled/expired, Weighted-Average Exercise Price | $ / shares	45.82
Outstanding at end of year, Weighted-Average Exercise Price | $ / shares	$ 0