Derivative Financial Instruments (Pretax Gains and Losses on Derivative Contracts Not Designated as Hedging Instruments Recognized in Earnings) (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 27, 2020	Dec. 29, 2019
Interest Expense [Member] \| Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 0.4	$ (10.9)
Interest Expense [Member] \| Long-term Debt [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Gain (Loss) on Derivative, Net	2.9	4.2
Interest and Other Income [Member] \| Diesel and Other Contracts [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains/(Losses) Recognized in Earnings	1.2	0.9
Interest and Other Income [Member] \| Foreign Currency Contract - Other [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains/(Losses) Recognized in Earnings	$ (0.8)	$ 3.4

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5618551-113959

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4CC
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109998890-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959

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