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Condensed Balance Sheets (Parenthetical) (USD $)
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Jun. 30, 2011
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Dec. 31, 2010
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| Condensed Balance Sheets | ||
| Preferred stock, par value (in dollars per share) | $ 0.01 | $ 0.01 |
| Preferred stock, Authorized shares | 5,000,000 | 5,000,000 |
| Preferred stock, Issued shares | 0 | 0 |
| Preferred stock, Outstanding shares | 0 | 0 |
| Common stock, par value (in dollars per share) | $ 0.01 | $ 0.01 |
| Common stock, Authorized shares | 100,000,000 | 100,000,000 |
| Common stock, Issued shares | 52,487,555 | 52,163,629 |
| Common stock, Outstanding shares | 52,487,555 | 52,163,629 |
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- Definition
Face amount or stated value of common stock per share; generally not indicative of the fair market value per share. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Face amount or stated value per share of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer); generally not indicative of the fair market value per share. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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