Schedule Of Changes In Unrecognized Tax Position (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2012	Jan. 31, 2011
Reconciliation of Unrecognized Tax Benefits [Line Items]
Beginning Balance	$ 50,696	$ 39,910
Gross increases-tax positions in prior period	647	6,771
Gross decreases-tax positions in prior period	(189)	(931)
Gross increases-tax positions in current period	3,484	6,099
Settlements		(141)
Lapse of statute of limitations	(12,084)	(3,481)
Cumulative translation adjustment	(649)	2,469
Ending Balance	$ 41,905	$ 50,696

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Unrecognized Tax Benefits Cumulative Translation Adjustment

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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 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 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.

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

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