Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 30, 2011	Nov. 30, 2010	Nov. 30, 2011	Nov. 30, 2010
Comprehensive Income
Net income	$ 17,532	$ 16,814	$ 34,181	$ 30,488
Other comprehensive income (loss)
Cumulative translation adjustments	(872)	972	(774)	1,082
Unrealized loss on derivatives, net of tax	(221)		(2,736)
Total comprehensive income	$ 16,439	$ 17,786	$ 30,671	$ 31,570

The change in equity [net assets] of a business enterprise during a period from transactions and other events and circumstances from non-owner sources which are attributable to the economic entity, including both controlling (parent) and noncontrolling interests. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, including any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

+ References+ Details

Change in accumulated gains and losses from derivative instrument designated and qualifying as the effective portion of cash flow hedges, net of tax effect. The after tax effect change includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

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- Definition

The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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