Note 3 - Debt - Summary of Debt Outstanding (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Long-term debt, gross	$ 175,000	$ 197,975
Debt discount and issuance costs	(7,115)	(5,244)
Less: Current portion of long-term debt	0	(27,797)
Total long-term debt	167,885	164,934
The 8.00% Senior Secured Notes due August 2022 [Member]
Long-term debt, gross	0	147,049
Troms Offshore [Member] \| NOK Denominated Notes Due January 2026 [Member]
Long-term debt, gross	175,000	0
Troms Offshore [Member] \| NOK Denominated Notes Due May 2024 [Member]
Long-term debt, gross	0	20,513
Troms Offshore [Member] \| USD Denominated Notes Due January 2027 [Member]
Long-term debt, gross	$ 0	$ 30,413

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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