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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.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 falsefalseCommon Shares, issued shares9false0us-gaap_TreasuryStockSharesus-gaaptruenainstantNo definition available.falsefalsefalsefalsefalsefalsefalsefalsefalsefalseterselabel1truefalsefalse19099091909909falsefalsefalsefalsefalse2truefalsefalse20530282053028falsefalsefalsefalsefalseSharesxbrli:sharesItemTypesharesNumber 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. 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