Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - $ / shares shares in Thousands	Mar. 31, 2022	Dec. 31, 2021
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	480,000	480,000
Common stock, shares issued (in shares)	121,600	120,800
Common stock, shares outstanding (in shares)	121,600	120,800
Treasury stock, shares (in shares)	541,258	346,126
Preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred stock, shares authorized (in shares)	500	500
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Series A Convertible Preferred Stock [Member]
Temporary equity, liquidation preference (in dollars per share)	$ 1,000	$ 1,000
Temporary equity, shares issued (in shares)	75,938	73,713
Temporary equity, shares outstanding (in shares)	75,938	73,713
Series B Convertible Preferred Stock [Member]
Temporary equity, liquidation preference (in dollars per share)	$ 1,000	$ 1,000
Temporary equity, shares issued (in shares)	72,556	70,433
Temporary equity, shares outstanding (in shares)	72,556	70,433
Series C Convertible Preferred Stock [Member]
Temporary equity, liquidation preference (in dollars per share)	$ 1,000	$ 1,000
Temporary equity, shares issued (in shares)	54,587	42,490
Temporary equity, shares outstanding (in shares)	54,587	42,490

Face amount or stated value per share of common stock.

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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 per share liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Number 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. This stock has no voting rights and receives no dividends.

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