Financial Instruments and Risk Management - Additional Information (Details) - USD ($)	3 Months Ended	12 Months Ended
Dec. 26, 2020	Sep. 26, 2020
Derivatives, Fair Value [Line Items]
Maximum maturity period of highly liquid investment considered as cash equivalents	3 months
Interest Rate Risk [Abstract]
Cash collateral	$ 0	$ 4,718,000
Commodity Contract [Member]
Interest Rate Risk [Abstract]
Weighted average maturity of outstanding commodity-related derivatives	3 months	6 months
Federal Funds Rate [Member]
Interest Rate Risk [Abstract]
Description of applicable interest rate on borrowings	Federal Funds Rate
Basis spread (in hundredths)	0.50%
LIBOR [Member]
Interest Rate Risk [Abstract]
Description of applicable interest rate on borrowings	LIBOR
Basis spread (in hundredths)	1.00%

Maximum maturity period of highly liquid investment considered as cash equivalents.

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226016-175313

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=d3e41678-113959

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- References

No definition available.

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- Details

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