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No definition available.

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Debt - Additional Information (Detail) - USD ($)			3 Months Ended		6 Months Ended		12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Jan. 26, 2023	Apr. 28, 2022	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022	Sep. 30, 2022
Debt Instrument [Line Items]
Long-term Debt, Gross			$ 597,000,000		$ 597,000,000		$ 600,000,000
Deferred financing cost			4,354,000		$ 4,354,000		$ 4,712,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt instrument maturity date					Mar. 31, 2026
Debt instrument, basis spread on variable rate					0.10%		0.10%
Deferred financing cost			800,000		$ 800,000		$ 900,000
Aggregate maximum borrowing capacity			150,000,000.0		150,000,000.0
Outstanding letters of credit			2,800,000		2,800,000		$ 2,800,000
Available borrowing capacity			100,000,000.0		$ 100,000,000.0
Debt instrument interest rate description					interest rate has been reduced by 25 basis points to (i) for ABR borrowings, the highest of (a) the Federal Funds Rate plus 50 basis points, (b) the prime rate and (c) the LIBOR as of such date for a deposit in U.S. dollars with a maturity of one month plus 100 basis points, plus, in each case, a spread of 25 to 75 basis points, based on average historical availability, or (ii) for Eurocurrency borrowings, adjusted LIBOR plus a spread of 125 to 175 basis points, based on average historical availability.
Debt instrument, description of variable rate basis					SOFR + 0.1%		SOFR + 0.1%
Line of credit facility, commitment fee description					If the average daily used percentage is greater than 50%, the commitment fee equals 25 basis points, and if the average daily used percentage is less than or equal to 50%, the commitment fee equals 37.5 basis points.
Line of credit facility, commitment fee amount			100,000	$ 100,000	$ 300,000	$ 200,000
Debt instrument, covenant description					(i) 10% of the lesser of the aggregate commitments under the Revolving Credit Facility and the borrowing base, and (ii) $12.5 million.
Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt instrument maturity date					Mar. 31, 2026
Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt instrument maturity date					May 09, 2022
Revolving Credit Facility [Member] \| CPG International LLC [Member]
Debt Instrument [Line Items]
Outstanding letters of credit			0		$ 0		$ 0
Available borrowing capacity			147,200,000		$ 147,200,000
Debt instrument, covenant description					CPG International LLC is also required to make mandatory prepayments (i) when aggregate borrowings exceed commitments or the applicable borrowing base and (ii) during “cash dominion,” which occurs if (a) the availability under the Revolving Credit Facility is less than the greater of (i) $12.5 million and (ii) 10% of the lesser of (x) $150.0 million and (y) the borrowing base, for five consecutive business days or (b) certain events of default have occurred and are continuing.
Revolving Credit Facility [Member] \| CPG International LLC [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Maximum fixed charge coverage ratio					100.0
Revolving Credit Facility [Member] \| CPG International LLC [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Minimum fixed charge coverage ratio					100.0
Revolving Credit Facility [Member] \| Abr Borrowings
Debt Instrument [Line Items]
Debt instrument interest rate description					(i) for ABR borrowings, the highest of (a) the Federal Funds Rate plus 50 basis points, (b) the prime rate and (c) the LIBOR as of such date for a deposit in U.S. dollars with a maturity of one month plus 100 basis points, plus, in each case, a spread of 25 to 75 basis points, based on average historical availability
Revolving Credit Facility [Member] \| Eurocurrency Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument interest rate description					for Eurocurrency borrowings, adjusted LIBOR plus a spread of 125 to 175 basis points, based on average historical availability
Federal Funds Rate \| Revolving Credit Facility [Member] \| Abr Borrowings
Debt Instrument [Line Items]
Debt instrument, description of variable rate basis					Federal Funds Rate plus 50 basis points
Team SOFR \| Revolving Credit Facility [Member] \| CPG International LLC [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	0.10%
Prime Rate [Member] \| Revolving Credit Facility [Member] \| Abr Borrowings
Debt Instrument [Line Items]
Debt instrument, description of variable rate basis					prime rate
London Interbank Offered Rate (LIBOR) [Member] \| Revolving Credit Facility [Member] \| Abr Borrowings
Debt Instrument [Line Items]
Debt instrument, description of variable rate basis					LIBOR as of such date for a deposit in U.S. dollars with a maturity of one month plus 100 basis points, plus, in each case, a spread of 25 to 75 basis points
London Interbank Offered Rate (LIBOR) [Member] \| Revolving Credit Facility [Member] \| Eurocurrency Borrowings [Member]
Debt Instrument [Line Items]
Debt instrument, description of variable rate basis					LIBOR plus a spread of 125 to 175 basis points
2022 Term Loan Agreement
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 600,000,000.0	597,000,000.0		$ 597,000,000.0		$ 600,000,000.0
Debt instrument maturity date		Apr. 28, 2029			Apr. 28, 2029
Percentage of principal amount to be repaid by way of instalments		0.25%
Debt instrument, basis spread on variable rate					2.50%		2.50%
Deferred financing cost			$ 4,400,000		$ 4,400,000		$ 4,700,000
Debt instrument, description of variable rate basis					SOFR + 2.50% + 0.1%		SOFR + 2.50% + 0.1%
2022 Term Loan Agreement \| Federal Funds Rate \| Abr Borrowings
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		0.50%
2022 Term Loan Agreement \| Team SOFR \| Abr Borrowings
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		1.00%
Applicable margin rate		1.50%
2022 Term Loan Agreement \| Team SOFR \| SOFR Borrowings [Member]
Debt Instrument [Line Items]
Applicable margin rate		2.50%
2022 Term Loan Agreement \| Alternative Base Rate \| Abr Borrowings
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		1.50%