Segments - Summary of Residential and Commercial Segment Reporting Information (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Segment Reporting Information [Line Items]
Net sales to customers	$ 377,692	$ 396,255	$ 593,951	$ 655,963
Adjusted EBITDA
Total Adjusted EBITDA for reporting segments	88,204	107,025	119,365	181,204
Unallocated net expenses	(15,394)	(16,104)	(31,455)	(31,763)
Adjustments to Income before income tax provision
Depreciation and amortization	(31,635)	(29,042)	(65,475)	(57,124)
Stock-based compensation costs	(5,626)	(4,928)	(9,583)	(8,944)
Acquisition costs	1,421	5,136	3,856	5,633
Other costs	(415)	(177)	(1,148)	(662)
Interest expense, net	(10,774)	(4,010)	(20,073)	(8,158)
Income (loss) before income tax provision	22,939	47,628	(12,225)	68,920
Residential [Member]
Segment Reporting Information [Line Items]
Net sales to customers	342,116	350,358	521,600	571,491
Adjusted EBITDA
Total Adjusted EBITDA for reporting segments	80,375	98,350	106,382	167,781
Commercial [Member]
Segment Reporting Information [Line Items]
Net sales to customers	35,576	45,897	72,351	84,472
Adjusted EBITDA
Total Adjusted EBITDA for reporting segments	$ 7,829	$ 8,675	$ 12,983	$ 13,423