Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Related Party Transaction [Line Items]
Total revenues	$ 1,772,630	$ 1,936,310	$ 1,744,822
Accounts receivable, net	73,269	113,175
Accounts payable	32,106	27,113
Tax receivable agreement liability	40,600	43,100
Affiliated Entity
Related Party Transaction [Line Items]
Purchase of inventories	124,400	94,300	84,200
Related party expenses incurred	2,500	2,100	2,800
Accounts payable	6,000	4,700
Tax receivable agreement liability	36,200	38,700
Affiliated Entities and Individuals
Related Party Transaction [Line Items]
Total revenues	4,000	1,100	6,300
Costs and expenses, related party	100	100	200
Tax receivable agreement, payments	$ 2,400	$ 2,200	$ 800