Share Repurchases (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended				9 Months Ended			12 Months Ended
	Feb. 28, 2016		Nov. 29, 2015	Feb. 22, 2015	Feb. 28, 2016		Feb. 22, 2015	May. 31, 2015
Accelerated Share Repurchases [Line Items]
Shares purchased, shares	1.1	[1]		3.7	10.6	[1]	22.3
Shares purchased, aggregate purchase price	$ 64.5			$ 192.9	$ 601.8		$ 1,161.7
Fair value of treasury stock acquired					$ 601.8			$ 1,161.9
Treasury Stock [Member]
Accelerated Share Repurchases [Line Items]
Shares purchased, shares					10.6			22.3
Fair value of treasury stock acquired					$ 601.8			$ 1,161.9
Second Quarter 2016 Accelerated Share Repurchases [Member]
Accelerated Share Repurchases [Line Items]
Shares purchased, shares	0.2				3.9
Cash paid to unrelated third party fiinancial institution			$ 225.0
Second Quarter 2016 Accelerated Share Repurchases [Member] | Treasury Stock [Member]
Accelerated Share Repurchases [Line Items]
Shares purchased, shares			3.7
Shares purchased, aggregate purchase price			$ 213.3
Adjustment to be made upon completion of the ASR	$ (11.7)
Second Quarter 2016 Accelerated Share Repurchases [Member] | Additional Paid-In Capital [Member]
Accelerated Share Repurchases [Line Items]
Shares purchased, aggregate purchase price			$ 11.7
Adjustment to be made upon completion of the ASR	$ 11.7

[1] The number of shares repurchased during the third quarter of fiscal 2016 and nine-month period ended February 28, 2016 include 0.2 million and 3.9 million shares, respectively, repurchased under an ASR agreement.