Accrued Expenses and Other Current Liabilities - Additional Information (Details) - USD ($) $ in Millions	Dec. 28, 2024	Sep. 28, 2024	Dec. 30, 2023
Payables and Accruals [Abstract]
Capital expenditures included in other accrued liabilities	$ 0.3	$ 1.0	$ 0.7

Capital expenditures included in other accrued liabilities current.

No definition available.

Name:	lesl_CapitalExpendituresIncludedInOtherAccruedLiabilitiesCurrent
Namespace Prefix:	lesl_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant