Note 4 - Indebtedness - Summary of Debt Outstanding (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Long-term debt, gross	$ 197,975	$ 297,659
Debt premium and discount, net	(5,244)	(8,725)
Less: Current portion of long-term debt	(27,797)	(9,890)
Total long-term debt	164,934	279,044
The 8.00% Senior Secured Notes due August 2022 [Member]
Long-term debt, gross	147,049	224,793
NOK Denominated Notes Due May 2024 [Member] \| Troms Offshore [Member]
Long-term debt, gross	5,954	10,260
NOK Denominated Notes Due January 2026 [Member] \| Troms Offshore [Member]
Long-term debt, gross	14,559	20,788
USD Denominated Notes Due January 2027 [Member] \| Troms Offshore [Member]
Long-term debt, gross	14,744	20,273
USD Denominated Notes Due April 2027 [Member] \| Troms Offshore [Member]
Long-term debt, gross	$ 15,669	$ 21,545

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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