Long-Term Borrowings - Additional Information (Details) - USD ($)		6 Months Ended
	Mar. 05, 2020	Mar. 26, 2022	Sep. 25, 2021
Debt Instrument [Line Items]
Ownership interest in Suburban Energy Finance Corp (in hundredths)		100.00%
Long-term borrowings		$ 1,134,500,000	$ 1,132,000,000
Consolidated fixed charge coverage ratio, minimum		1.75
Long-term debt maturities, 2022		$ 0
Long-term debt maturities, 2023		0
Long-term debt maturities, 2024		0
Long-term debt maturities, 2025		134,500,000
Long-term debt maturities, 2026		0
Long-term debt maturities, 2026 and thereafter		$ 1,000,000,000
Federal Funds Rate [Member]
Debt Instrument [Line Items]
Description of applicable interest rate on borrowings		Federal Funds Rate
Margin over basis rate (in hundredths)		0.50%
LIBOR [Member]
Debt Instrument [Line Items]
Description of applicable interest rate on borrowings		LIBOR
Margin over basis rate (in hundredths)		1.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Consolidated interest coverage ratio, minimum		2.5
Total consolidated leverage ratio		5.75
Senior secured unconsolidated leverage ratio maximum		3.25
Amended Credit Agreement Due 2025 [Member]
Debt Instrument [Line Items]
Weighted average interest rate (in hundredths)		2.81%
Amended Credit Agreement Due 2025 [Member] | Federal Funds Rate [Member]
Debt Instrument [Line Items]
Description of applicable interest rate on borrowings		Federal Funds Rate
Margin over basis rate (in hundredths)		0.50%
Amended Credit Agreement Due 2025 [Member] | LIBOR [Member]
Debt Instrument [Line Items]
Description of applicable interest rate on borrowings		LIBOR
Margin over basis rate (in hundredths)		1.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maturity date	Mar. 05, 2025	Mar. 05, 2025
Long-term borrowings		$ 134,500,000	132,000,000
Standby letters of credit issued under the Revolving Credit Facility		$ 48,862,000
Standby letters of credit issued under the Revolving Credit Facility, expiration date		Jan. 28, 2023
Revolving Credit Facility [Member] | Third Amended and Restated Credit [Member]
Debt Instrument [Line Items]
Long-term borrowings		$ 134,500,000	$ 132,000,000
Credit Facility, maximum amount	$ 500,000,000
5.875% Senior Notes due March 1, 2027 [Member]
Debt Instrument [Line Items]
Stated interest rate (in hundredths)		5.875%	5.875%
Maturity date		Mar. 01, 2027
5.0 % Senior Notes due June 1, 2031 [Member]
Debt Instrument [Line Items]
Stated interest rate (in hundredths)		5.00%	5.00%
Maturity date		Jun. 01, 2031
Date public offering completed		May 24, 2021
Percentage of principal amount at which debt was issued (in hundredths)		100.00%
Aggregate principal amount		$ 650,000,000
5.5% Senior Notes due June 1, 2024 [Member]
Debt Instrument [Line Items]
Stated interest rate (in hundredths)		5.50%
5.75% Senior Notes due March 1, 2025 [Member]
Debt Instrument [Line Items]
Stated interest rate (in hundredths)		5.75%
Senior Notes [Member] | 5.875% Senior Notes due March 1, 2027 [Member]
Debt Instrument [Line Items]
Stated interest rate (in hundredths)		5.875%
Maturity date		Mar. 01, 2027
Date public offering completed		Feb. 14, 2017
Ownership interest in Suburban Energy Finance Corp (in hundredths)		100.00%
Long-term borrowings		$ 350,000,000	$ 350,000,000
Percentage of principal amount at which debt was issued (in hundredths)		100.00%
Percentage of the principal amount repurchase offer under change of control provision (in hundredths)		101.00%
Repurchase of debt due to decline in rating after consummation of change of control, period		90 days
Senior Notes [Member] | 7.375% Senior Notes due August 1, 2021 [Member]
Debt Instrument [Line Items]
Stated interest rate (in hundredths)		7.375%
Senior Notes [Member] | 5.0 % Senior Notes due June 1, 2031 [Member]
Debt Instrument [Line Items]
Long-term borrowings		$ 650,000,000	$ 650,000,000
Percentage of the principal amount repurchase offer under change of control provision (in hundredths)		101.00%
Repurchase of debt due to decline in rating after consummation of change of control, period		90 days