Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Apr. 30, 2011	Jan. 31, 2011	Apr. 30, 2010
Condensed Consolidated Balance Sheets
Accounts receivable, allowance for doubtful accounts	$ 1,078	$ 1,015	$ 1,220
Preferred shares, par value	$ 0.0001	$ 0.0001	$ 0.0001
Preferred shares, shares authorized	10,000,000	10,000,000	10,000,000
Preferred shares, shares issued	0	0	0
Common shares, par value	$ 0.0001	$ 0.0001	$ 0.0001
Common shares, shares authorized	200,000,000	200,000,000	200,000,000
Common shares, shares issued	159,667,925	164,413,427	169,376,345
Common shares, shares outstanding	159,667,925	164,413,427	169,376,345

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

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-Name Regulation S-X (SX)
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Face amount or stated value of common stock per share; generally not indicative of the fair market value per share.

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