Income Taxes (Details 3) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jan. 31, 2013	Jan. 31, 2012
Reconciliation of the beginning and ending amounts of unrecognized tax benefits
Balance at beginning of fiscal year	$ 3,590	$ 2,883
Increases related to current year tax positions	114	107
Increases related to prior year tax positions	199	631
Decreases related to prior year tax positions		(31)
Decreases related to lapsing of statute of limitations	(640)
Decreases related to settlements with taxing authorities	(496)
Balance at end of fiscal year	$ 2,767	$ 3,590

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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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