Note 5 - Stockholders' Equity and Dilutive Equity Instruments - Dilutive Equity Instruments (Details) - shares	Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2024
Common stock, shares outstanding (in shares)	49,481,018	51,461,472	52,487,862
Total (in shares)	50,292,070		53,335,022
Restricted Stock Units and Stock Options [Member]
Common stock shares reserved (in shares)	661,893		689,806
New Creditor Warrants [Member]
Common stock shares reserved (in shares)	76,175		76,175
GulfMark Creditor Warrants [Member]
Common stock shares reserved (in shares)	72,984		81,179

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

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