Significant Accounting Policies, Textual (Details)	12 Months Ended
Dec. 31, 2019 USD ($) segment	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Accounting Policies [Abstract]
Other comprehensive income/(loss)	$ 0	$ 0	$ 0
Provision for doubtful accounts	$ 0	0
Vessels, useful life	25 years
Assets held for sale	$ 0	0
Derivatives	$ 0	$ 0	$ 0
Effective income tax rate		4.00%
Number of reportable segments \| segment	1
Number of operating segments \| segment	1
Inventory [Line Items]
Inventories	$ 9,265,000	$ 4,139,000
Bunkers
Inventory [Line Items]
Inventories	5,422,000	0
Lubricants
Inventory [Line Items]
Inventories	$ 3,843,000	$ 4,139,000

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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