Estimated Future Minimum Lease Payments Receivable Related to Sales-Type Leases (Detail) (USD $) In Thousands, unless otherwise specified	May 31, 2013
Lease and Rental Expense [Line Items]
2014	$ 6,561
2015	2,726
2016	458
2017	117
Total intangible assets	$ 9,862

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Amount of minimum lease payments to be received by the lessor for capital leases.

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