Reconciliation of Changes in Uncertain Tax Positions (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Mar. 31, 2013
Reconciliation of Unrecognized Tax Benefits [Line Items]
Total amount of unrecognized tax benefits as of April 1, 2012	$ 121
Gross increases in unrecognized tax benefits as a result of tax positions taken during a prior period
Gross decreases in unrecognized tax benefits as a result of tax positions taken during a prior period
Gross increases in unrecognized tax benefits as a result of tax positions taken during the current period
Gross decreases in unrecognized tax benefits as a result of tax positions taken during the current period
Decreases in unrecognized tax benefits relating to settlements with taxing authorities
Reductions to unrecognized tax benefits as a result of lapse of statute of limitations
Total amount of unrecognized tax benefits as of March 31, 2013	$ 121

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

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The gross amount of decreases 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.

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

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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