Revenue from contract with customers - Additional Information (Details) $ in Millions	6 Months Ended
Jun. 30, 2026 USD ($)
Revenue from Contract with Customer [Abstract]
Equipment deposits	$ 7.3
Deferred revenue expected recognition period (in months)	12 months

Contract With Customer, Liability, Customer Deposit Expected To Recognized Period

No definition available.

Name:	plnt_ContractWithCustomerLiabilityCustomerDepositExpectedToRecognizedPeriod
Namespace Prefix:	plnt_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration