Vessels, Net, Net Book Value (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Accumulated Depreciation [Abstract]
Depreciation for the period	$ (6,983)	$ (6,187)
Net book value	357,165		$ 257,110
Vessels [Member]
Cost [Abstract]
Beginning balance	307,870	292,280	292,280
Additions	102,909		15,590
Transfer to vessels held for sale	(17,127)		0
Ending balance	393,652		307,870
Accumulated Depreciation [Abstract]
Beginning balance	(51,133)	$ (38,499)	(38,499)
Depreciation for the period	(6,950)		(12,634)
Transfer to vessels held for sale	6,222		0
Ending balance	(51,861)		(51,133)
Net book value	$ 341,791		$ 256,737

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 of decrease in accumulated depreciation, depletion and amortization as a result of sale or disposal of property, plant and equipment.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of acquisition of long-lived, 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, furniture and fixtures, and computer 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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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services 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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Amount of increase (decrease) of physical assets used in the normal conduct of business and not intended for resale, from reclassification, impairment, donation, or changes classified as other. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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