Preferred units - Board Rights, Protective Provisions (Details)	Jul. 31, 2025 USD ($) director shares
Preferred units
Minimum preferred units outstanding to designate director to board by unit holders \| shares	140,000
Number of director to the Board permitted to designate by unit holders \| director	1
Minimum value outstanding for director appointment \| $	$ 35

Threshold number of preferred units outstanding to designate director to board by unit holders

No definition available.

Name:	fgp_ThresholdNumberOfPreferredUnitsOutstandingToDesignateDirectorToBoardByUnitHolders
Namespace Prefix:	fgp_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant