Financial Instruments, Risk Management Activities, and Fair Values (Schedule of gains and losses on hedges) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 23, 2014	Nov. 24, 2013	Nov. 23, 2014	Nov. 24, 2013
Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in other comprehensive income (OCI)	$ 7.3	$ (10.2)	$ 5.8	$ 7.9
Amount of gain (loss) reclassified from AOCI into earnings	(2.4)	1.3	(6.7)	3.4
Amount of gain (loss) recognized in earnings	0.1	0	0.1	(0.2)
Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	1.2	1.5	0.9	0.3
Not Designated as Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	(36.8)	(4.6)	(75.5)	(21.5)
Interest Rate Contracts [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in other comprehensive income (OCI)	0	(3.7)	0	10.7
Amount of gain (loss) reclassified from AOCI into earnings	(2.6)	(3.1)	(5.2)	(6.1)
Amount of gain (loss) recognized in earnings	0	0	0	0
Interest Rate Contracts [Member] \| Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	1.2	1.5	0.9	0.3
Interest Rate Contracts [Member] \| Not Designated as Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	0	0	0	0
Foreign Exchange Contracts [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in other comprehensive income (OCI)	7.3	(6.5)	5.8	(2.8)
Amount of gain (loss) reclassified from AOCI into earnings	0.2	4.4	(1.5)	9.5
Amount of gain (loss) recognized in earnings	0.1	0	0.1	(0.2)
Foreign Exchange Contracts [Member] \| Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	0	0	0	0
Foreign Exchange Contracts [Member] \| Not Designated as Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	2.3	(6.0)	0.9	(11.1)
Equity Contracts [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in other comprehensive income (OCI)	0	0	0	0
Amount of gain (loss) reclassified from AOCI into earnings	0	0	0	0
Amount of gain (loss) recognized in earnings	0	0	0	0
Equity Contracts [Member] \| Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	0	0	0	0
Equity Contracts [Member] \| Not Designated as Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	1.1	5.1	5.2	5.6
Commodity Contracts [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in other comprehensive income (OCI)	0	0	0	0
Amount of gain (loss) reclassified from AOCI into earnings	0	0	0	0
Amount of gain (loss) recognized in earnings	0	0	0	0
Commodity Contracts [Member] \| Fair Value Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	0	0	0	0
Commodity Contracts [Member] \| Not Designated as Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) recognized in earnings	$ (40.2)	$ (3.7)	$ (81.6)	$ (16.0)

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4C

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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