Long-term Debt - Schedule of Long-term Debt (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Mar. 29, 2019	Sep. 28, 2018
Debt Instrument [Line Items]
Less: Deferred Financing Fees	$ (4,249)	$ (4,998)
Other	0	36
Total Long-term debt, net	2,841,536	2,144,167
Term Loan Facility
Debt Instrument [Line Items]
Total Long-term debt, net	1,500,000	1,500,000
Senior Notes, Series A
Debt Instrument [Line Items]
Total Long-term debt, net	$ 190,000	190,000
Interest Rate	4.27%
Senior Notes, Series B
Debt Instrument [Line Items]
Total Long-term debt, net	$ 180,000	180,000
Interest Rate	4.42%
Senior Notes, Series C
Debt Instrument [Line Items]
Total Long-term debt, net	$ 130,000	130,000
Interest Rate	4.52%
New Credit Agreement
Debt Instrument [Line Items]
Total Long-term debt, net	$ 845,785	0
Revolving Credit Facility
Debt Instrument [Line Items]
Total Long-term debt, net	$ 0	$ 149,129
Minimum \| Eurodollar
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	1.00%
Minimum \| Eurodollar \| Revolving Credit Facility
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	0.875%
Minimum \| Base Rate
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	0.00%
Minimum \| Base Rate \| Revolving Credit Facility
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	0.00%
Minimum \| LIBOR
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	3.87%	3.71%
Minimum \| LIBOR \| Revolving Credit Facility
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	1.38%	1.38%
Maximum \| Eurodollar
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	1.50%
Maximum \| Eurodollar \| Revolving Credit Facility
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	1.50%
Maximum \| Base Rate
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	0.50%
Maximum \| Base Rate \| Revolving Credit Facility
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	0.50%
Maximum \| LIBOR \| Revolving Credit Facility
Debt Instrument [Line Items]
Margin added to variable rate interest rate (percentage)	3.78%	3.47%

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

No definition available.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

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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.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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- Definition

Amount of long-term debt classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Topic 942
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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