Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical)	Sep. 30, 2011	Dec. 31, 2010
Share capital (Note 7)
First preference shares, shares authorized	5,000,000	5,000,000
Common shares, shares authorized	500,000,000	500,000,000
Common shares, shares issued	49,363,310	51,154,392
Common shares, shares outstanding	49,363,310	51,154,392

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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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. Shares outstanding equals shares issued minus shares held in treasury and other adjustments, if any.

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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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