Condensed Consolidated Balance Sheets (Parentheticals) - $ / shares	Mar. 31, 2020	Dec. 31, 2019
Class of stock information
Common stock, par value per share (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized	450,000,000	450,000,000
Common stock, shares issued	204,444,835	203,452,812
Common stock, shares outstanding	204,444,835	203,452,812

Face amount or stated value per share of common stock.

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

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-Name Accounting Standards Codification
-Topic 505
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