Commitments and Contingent Liabilities (Details)	12 Months Ended
Dec. 31, 2020 ship
Commitments and Contingencies Disclosure [Abstract]
Number of vessels to be delivered on a Norwegian Sales Form basis	3

Number Of Shipping Vessels Delivered On A Norwegian Sales Form Basis

No definition available.

Name:	flng_NumberOfShippingVesselsDeliveredOnANorwegianSalesFormBasis
Namespace Prefix:	flng_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration