UNAUDITED CONSOLIDATED BALANCE SHEETS (Parenthetical)	Jun. 30, 2012	Dec. 31, 2011
Shareholders' equity:
Capital stock, shares outstanding (in shares)	72,207,144	71,503,883

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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