Comprehensive Income (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net income	$ 22,679	$ 25,992	$ 39,664	$ 38,637
Foreign currency translation adjustment, net of tax	(18,327)	(1,263)	(19,153)	2,427
Total comprehensive income	$ 4,352	$ 24,729	$ 20,511	$ 41,064

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 reporting entity. It includes all changes in equity during a period except those resulting from investments by owners and distributions to owners, but excludes any and all transactions which are directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent.

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-Name Accounting Standards Codification

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-Glossary Other Comprehensive Income

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+ Details

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

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+ Details

- Definition

Adjustment that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency of the reporting entity, net of tax.

+ References

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+ Details