Intangible Assets/Liabilities - Charter Agreements - Schedule of Intangible Liabilities (Table) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Intangible Liability Disclosure [Abstract]
Opening balance	$ 10,482	$ 12,527
Amortization in period	(2,012)	(2,045)
Closing balance	$ 8,470	$ 10,482

Non current portion of the excess of the market value of vessel charters over contracted value of the charters at the date of merger. The intangible lease liability is amortized as an increase in time charter revenue over the remaining term of the relevant charter.

No definition available.

Name:	gsl_IntangibleLiabilityCharterAgreementsNoncurrent
Namespace Prefix:	gsl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant