Sales-Type Leases (Details 1) (USD $) In Thousands, unless otherwise specified	May 31, 2012
Estimated future minimum lease payments receivable related to sales-type leases
2013 (remaining)	$ 5,619
2014	3,966
2015	1,473
2016	170
2017	115
Total	$ 11,343

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

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

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-Name Accounting Standards Codification

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Amount of minimum lease payments to be received by the lessor in the fifth fiscal year following the latest fiscal year for capital leases.

+ References

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

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Amount of minimum lease payments to be received by the lessor in the fourth fiscal year following the latest fiscal year for capital leases.

+ References

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

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Amount of minimum lease payments to be received by the lessor in the third fiscal year following the latest fiscal year for capital leases.

+ References

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

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Amount of minimum lease payments to be received by the lessor in the second fiscal year following the latest fiscal year for capital leases.

+ References

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

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Amount of minimum lease payments to be received by the lessor in the remainder of the fiscal year following the latest fiscal year ended for capital leases.

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