Minimum Lease Payments Receivable and Net Investment (Detail) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2013	May 31, 2013
Sales Type Lease Receivables [Line Items]
Gross minimum lease payments receivable	$ 9,417	$ 9,862
Less - unearned interest	(383)	(425)
Net investment in sales-type lease receivables	$ 9,034	$ 9,437

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The net investment in sales type leases as of the balance sheet date consisting of: (a) minimum lease payments on sales type leases and (b) unguaranteed residual value; less: (i) executory costs, (ii) unearned income, and (iii) the accumulated allowance for uncollectible minimum lease payments.

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+ Details

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- Definition

The remaining (unamortized) difference between the gross investment in a sales-type lease and the cost or carrying amount of the leased property as of the balance sheet date.

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- Definition

Amount of remaining payments as of the balance sheet date that lessees are obligated to make or can be required to make under sales-type leases, including any guarantee of residual value and executory costs. The amount also includes any guaranteed rental payments by an unrelated third-party provided that are financially capable of making such payments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 25

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=7661868&loc=d3e34102-112682

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