Subsequent Events (Details) - Subsequent Event [Member] $ in Thousands	Jul. 27, 2021 USD ($)	Jul. 23, 2021 Subsidiary
Debt Financings [Abstract]
Number of ship-owning subsidiaries entering into term loan facility \| Subsidiary		4
$40.75 Million Hamburg Facility [Member]
Debt Financings [Abstract]
Face amount \| $	$ 40,750
Term of loan	5 years

Face (par) amount of debt instrument at time of issuance.

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Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant