Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Number of shares authorized for issuance under share-based payment arrangement.

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Equity Incentive Plan (Details) - USD ($) $ / shares in Units, $ in Thousands		6 Months Ended
	Jan. 18, 2021	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
General and Administrative Expenses [Member] \| Board of Directors and Certain Employees [Member]
Equity Incentive Plan [Abstract]
Stock-based compensation expense		$ 1,850	$ 578
Voyage Expenses [Member] \| Non-Employees [Member]
Equity Incentive Plan [Abstract]
Stock-based compensation expense		81	$ 11
Restricted Stock [Member]
Unrecognized Cost for Non-vested Shares [Abstract]
Unrecognized cost for non-vested shares		$ 1,063		$ 119
Recognition period for unrecognized cost for non-vested shares		1 year 6 months
Equity Incentive Plan [Member]
Equity Incentive Plan [Abstract]
Shares reserved for issuance (in shares)	4,000,000
Equity Incentive Plan [Member] \| Restricted Stock [Member] \| Awarded January 18, 2021 [Member]
Equity Incentive Plan [Abstract]
Shares granted (in shares)	3,600,000
Weighted average grant date fair value (in dollars per share)	$ 0.81
Equity Incentive Plan [Member] \| Restricted Stock [Member] \| Awarded January 18, 2021 [Member] \| Non-Executive Members of Board of Directors [Member]
Equity Incentive Plan [Abstract]
Shares granted (in shares)	1,400,000
Equity Incentive Plan [Member] \| Restricted Stock [Member] \| Awarded January 18, 2021 [Member] \| Executive Officers [Member]
Equity Incentive Plan [Abstract]
Shares granted (in shares)	950,000
Equity Incentive Plan [Member] \| Restricted Stock [Member] \| Awarded January 18, 2021 [Member] \| Certain Other Non-Executive Employees [Member]
Equity Incentive Plan [Abstract]
Shares granted (in shares)	1,100,000
Equity Incentive Plan [Member] \| Restricted Stock [Member] \| Awarded January 18, 2021 [Member] \| Non-Employees [Member]
Equity Incentive Plan [Abstract]
Shares granted (in shares)	150,000