Guarantees	9 Months Ended
Feb. 29, 2012
Guarantees [Abstract]
Guarantees	NOTE E — Guarantees We do not have guarantees that we believe are reasonably likely to have a material current or future effect on our financial condition, changes in financial condition, revenues or expenses, results of operations, liquidity, capital expenditures or capital resources. However, as of February 29, 2012, we were party to an operating lease for an aircraft in which we have guaranteed a residual value at the termination of the lease. The maximum obligation under the terms of this guarantee was approximately $15,174,000 at February 29, 2012. We have also guaranteed the repayment of a $5,000,000 term loan entered into by one of our unconsolidated affiliates, ArtiFlex. Based on current facts and circumstances, we have estimated the likelihood of payment pursuant to these guarantees, and determined that the fair value of our obligation under each guarantee based on those likely outcomes is not material. We also had in place $10,350,000 of outstanding stand-by letters of credit as of February 29, 2012. These letters of credit were issued to third-party service providers and had no amounts drawn against them at February 29, 2012. The fair value of these guarantee instruments, based on premiums paid, was not material.

Guarantees

9 Months Ended

Feb. 29, 2012

NOTE E — Guarantees

We do not have guarantees that we believe are reasonably likely to have a material current or future effect on our financial condition, changes in financial condition, revenues or expenses, results of operations, liquidity, capital expenditures or capital resources. However, as of February 29, 2012, we were party to an operating lease for an aircraft in which we have guaranteed a residual value at the termination of the lease. The maximum obligation under the terms of this guarantee was approximately $15,174,000 at February 29, 2012. We have also guaranteed the repayment of a $5,000,000 term loan entered into by one of our unconsolidated affiliates, ArtiFlex. Based on current facts and circumstances, we have estimated the likelihood of payment pursuant to these guarantees, and determined that the fair value of our obligation under each guarantee based on those likely outcomes is not material.

We also had in place $10,350,000 of outstanding stand-by letters of credit as of February 29, 2012. These letters of credit were issued to third-party service providers and had no amounts drawn against them at February 29, 2012. The fair value of these guarantee instruments, based on premiums paid, was not material.