Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Mar. 31, 2011	Mar. 31, 2010
Current assets
Allowance for doubtful accounts	$ 13,388	$ 13,163
Shareholders' equity
Ordinary shares, par value
Ordinary shares, issued	830,745,010	843,208,876
Ordinary shares, outstanding	756,993,938	813,429,154
Treasury stock, shares	73,751,072	29,779,722

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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-Section 02
-Paragraph 4
-Article 5

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Issuance value per share of no-par value common stock; generally not indicative of the fair market value per share.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Total number of shares of common stock held by shareholders. May be all or portion of the number of common shares authorized. These shares represent the ownership interest of the common shareholders. Excludes common shares repurchased by the entity and held as Treasury shares. Shares outstanding equals shares issued minus shares held in treasury. Does not include common shares that have been repurchased.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Principles Board Opinion (APB)
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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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