Stock-Based Compensation (Range of Exercise Prices) (Details) (USD $)	12 Months Ended
May 31, 2013
$20.29 - 34.05 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number Outstanding (shares)	1,720,863
Outstanding Options, Average Remaining Option Life (years)	6 years 7 months 23 days
Outstanding Options, Weighted Average Exercise Price (dollars per share)	$ 27.01
Exercisable Options, Number Exercisable (shares)	352,058
Exercisable Options, Weighted Average Exercise Price (dollars per share)	$ 26.71
Exercise price range, lower limit (dollars per share)	$ 20.29
Exercise price range, upper limit (dollars per share)	$ 34.05
$34.06 - 37.83 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number Outstanding (shares)	1,338,274
Outstanding Options, Average Remaining Option Life (years)	7 years 4 months 21 days
Outstanding Options, Weighted Average Exercise Price (dollars per share)	$ 34.94
Exercisable Options, Number Exercisable (shares)	97,092
Exercisable Options, Weighted Average Exercise Price (dollars per share)	$ 36.28
Exercise price range, lower limit (dollars per share)	$ 34.06
Exercise price range, upper limit (dollars per share)	$ 37.83
$37.84 - 41.98 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number Outstanding (shares)	1,959,113
Outstanding Options, Average Remaining Option Life (years)	6 years 11 months 19 days
Outstanding Options, Weighted Average Exercise Price (dollars per share)	$ 38.59
Exercisable Options, Number Exercisable (shares)	377,057
Exercisable Options, Weighted Average Exercise Price (dollars per share)	$ 39.63
Exercise price range, lower limit (dollars per share)	$ 37.84
Exercise price range, upper limit (dollars per share)	$ 41.98
$41.99 - 49.30 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number Outstanding (shares)	2,867,388
Outstanding Options, Average Remaining Option Life (years)	7 years 2 months 12 days
Outstanding Options, Weighted Average Exercise Price (dollars per share)	$ 44.43
Exercisable Options, Number Exercisable (shares)	989,588
Exercisable Options, Weighted Average Exercise Price (dollars per share)	$ 43.11
Exercise price range, lower limit (dollars per share)	$ 41.99
Exercise price range, upper limit (dollars per share)	$ 49.30
$20.29 - 49.30 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number Outstanding (shares)	7,885,638
Outstanding Options, Average Remaining Option Life (years)	7 years 0 months 18 days
Outstanding Options, Weighted Average Exercise Price (dollars per share)	$ 37.60
Exercisable Options, Number Exercisable (shares)	1,815,795
Exercisable Options, Weighted Average Exercise Price (dollars per share)	$ 38.85
Exercise price range, lower limit (dollars per share)	$ 20.29
Exercise price range, upper limit (dollars per share)	$ 49.30

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Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ References

+ Details

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(c)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(1)(a, b)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ References

+ Details

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- Definition

Weighted average remaining contractual term of outstanding stock options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

+ Details

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