Note 12 - Properties and Equipment, Accrued Costs and Expenses, Other Current Liabilities and Other Liabilities - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Vessels and related equipment	$ 968,411	$ 1,051,558
Other properties and equipment	15,674	13,119
Property, Plant and Equipment, Gross, Ending Balance	984,085	1,064,677
Less accumulated depreciation and amortization	163,209	125,716
Properties and equipment, net	$ 820,876	$ 938,961

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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