Reconciliation of Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Income Tax [Line Items]
Unrecognized tax benefits, beginning balance	$ 12,945	$ 10,645	$ 10,750
Increases related to current year tax positions	6,296	5,032	2,896
Increases related to prior year tax positions	969	182	324
Increases related to prior year tax positions due to foreign currency translation	245		122
Decreases related to prior year tax positions due to foreign currency translation		(28)
Decreases related to prior year tax position settled			(3,145)
Lapse of statute of limitations	(3,970)	(2,886)	(302)
Unrecognized tax benefits, ending balance	$ 16,485	$ 12,945	$ 10,645

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Unrecognized Tax Benefits Decrease Resulting from Prior Year Tax Position Due to Foreign Currency Translation

+ References

No definition available.

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- Definition

Unrecognized tax benefits increase resulting from prior year tax position due to foreign currency translation

+ References

No definition available.

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- Definition

The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

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- Definition

The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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- Definition

This element represents the recognized expense for the amount of statutory penalties in the period in which the entity claims or expects to claim a tax position, in its tax return, that does not meet the minimum statutory threshold to avoid payment of penalties or, if not recognizing the expense in the period in which the tax return was initially filed, the expense is generally recognized in the period in which the enterprise's judgment about meeting the minimum statutory threshold changes.

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-Name Accounting Standards Codification

-Topic 740

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- Definition

The gross amount of increases in unrecognized tax benefits resulting from tax positions that have been or will be taken in the tax return for the current period, excluding amounts pertaining to examined tax returns.

+ References

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

-Publisher FASB

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- Definition

The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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