Sales-Type Leases - Minimum Lease Payments Receivable and Net Investment (Detail) - USD ($) $ in Thousands	Aug. 31, 2015	May. 31, 2015
Leases [Abstract]
Gross minimum lease payments receivable	$ 5,750	$ 6,109
Less – unearned interest	(205)	(233)
Net investment in sales-type lease receivables	$ 5,545	$ 5,876

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.

Name:	us-gaap_CapitalLeasesNetInvestmentInSalesTypeLeases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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.

+ References

+ Details

Name:	us-gaap_CapitalLeasesNetInvestmentInSalesTypeLeasesDeferredIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ References

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

+ Details

Name:	us-gaap_CapitalLeasesNetInvestmentInSalesTypeLeasesMinimumPaymentsToBeReceived
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- References

No definition available.

+ Details

Name:	us-gaap_LeasesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration