Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2020	Dec. 31, 2019
Preferred Stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	2,714,300	2,714,300
Preferred stock, par value (in usd per share)	$ 0.001
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common Stock, shares authorized (in shares)	235,000,000	175,000,000
Common Stock, shares issued (in shares)	101,417,441	96,189,074
Common stock, shares outstanding (in shares)	101,354,447	96,173,583
Treasury stock, shares (in shares)	62,994	15,491
SeriesA Non-Voting Convertible Preferred Stock
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred Stock, shares outstanding (in shares)	0	2,093,155
Series B Non-Voting Convertible Preferred Stock
Preferred stock, par value (in usd per share)	$ 0.001	$ 0.001
Preferred Stock, shares outstanding (in shares)	443	618

Face amount or stated value per share of common stock.

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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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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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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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