Debt - Additional Information (Detail)	12 Months Ended
Sep. 27, 2019 USD ($)
Debt Instrument [Line Items]
Debt instrument face amount	$ 700,000,000.0
Unamortized deferred financing costs	8,000,000.0
Term Loans
Debt Instrument [Line Items]
Unamortized deferred financing costs	7,400,000
Quarterly principal installments	$ 1,700,000
Maximum period for reinvestment of business divestiture proceeds	18 months
Maximum period for completion of reinvestment of business divestiture proceeds	6 months
Estimated fair value of term loans	$ 585,500,000
Term Loans \| Federal Funds Effective Swap Rate
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Term Loans \| One Month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Term Loans \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Term Loans \| Minimum \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Revolving Credit Facility
Debt Instrument [Line Items]
Unamortized deferred financing costs	$ 600,000
Credit Agreement \| Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity	160,000,000.0
Remaining borrowing capacity	$ 160,000,000.0

Debt Instrument, Payment Terms, Reinvestment Of Divestiture Of Business Proceeds, Transaction Completion, Period

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- Definition

Debt Instrument, Payment Terms, Reinvestment Of Divestiture of Business Proceeds, Period

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- Definition

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

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- Definition

Face (par) amount of debt instrument at time of issuance.

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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.

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Amount of the required periodic payments including both interest and principal payments.

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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.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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