Note 5 - Investment in Unconsolidated Affiliates - Related Party Transaction (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Angolan joint venture (Sonatide)	$ 0	$ 70,134
Sonatide	0	61,555
Due from affiliates, net of due to affiliates	0	8,579
Sonatide Marine Ltd [Member] \| ANGOLA
Angolan joint venture (Sonatide)	0	49,011
Sonatide	0	40,432
DTDW [Member] \| NIGERIA
Angolan joint venture (Sonatide)	0	21,123
Sonatide	$ 0	$ 21,123

The aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due within one year (or one business cycle).

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+ Details

- Definition

Carrying amount as of the balance sheet date of obligations due all related parties. For classified balance sheets, represents the current portion of such liabilities (due within one year or within the normal operating cycle if longer).

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