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Pension Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Nov. 30, 2012 | May 31, 2012
Pension Benefits, U.S. Plans |  |
Schedule of Pension and Other Postretirement Benefits Expected Benefit Payments [Line Items] |  |
Contribution to retirement plans in current fiscal year | $ 24.5 | $ 29.9
Reduction in contribution to retirement plans in current fiscal year | (5.4) |
Pension Benefits, Non-U.S. Plans |  |
Schedule of Pension and Other Postretirement Benefits Expected Benefit Payments [Line Items] |  |
Contribution to retirement plans in current fiscal year |  | $ 8.3

X
- Definition Defined Contribution Plan Increase Decrease + References No definition available. + Details
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- Details
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Balance Type: | na
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period. + References No definition available. + Details
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