Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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

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Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Fair value portion of contractual obligation to pay money on demand or on fixed or determinable dates.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash outflow for a long-term debt where the holder has highest claim on the entity's asset in case of bankruptcy or liquidation during the period.

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Fair Value Measurements (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Thousands	Mar. 28, 2020	Sep. 28, 2019	Sep. 29, 2018	Dec. 28, 2019	Dec. 29, 2018
Financial assets and liabilities at fair value
Term loans and senior notes, carrying value	$ 1,979,361			$ 1,879,783
Long-term Debt, Gross	1,998,875
Outstanding principal	1,998,875
Repayments of long-term debt	$ 1,125
Changes in level 3
Level 3 activity		$ 0	$ 0
5.25% Senior Notes due 2025
Financial assets and liabilities at fair value
Interest rate (as a percent)	5.25%	5.25%			5.25%
Face amount of senior notes		$ 900,000			$ 900,000
5.25% Senior Notes due 2027
Financial assets and liabilities at fair value
Interest rate (as a percent)		5.25%			5.25%
Carrying Value
Financial assets and liabilities at fair value
Long-term Line of Credit	$ 100,000
Carrying Value \| Tranche B Term Loans due 2026
Financial assets and liabilities at fair value
Term loans and senior notes, carrying value	446,766			447,820
Face amount of senior notes	448,900			450,000
Carrying Value \| 5.25% Senior Notes due 2025
Financial assets and liabilities at fair value
Term loans and senior notes, carrying value	902,697			902,832
Carrying Value \| 5.25% Senior Notes due 2027
Financial assets and liabilities at fair value
Term loans and senior notes, carrying value	550,000			550,000
Fair value measured on recurring basis \| Fair Value \| Level 2
Financial assets and liabilities at fair value
Term loans and senior notes, fair value	100,000
Fair value measured on recurring basis \| Fair Value \| Tranche B Term Loans due 2026 \| Level 2
Financial assets and liabilities at fair value
Term loans and senior notes, fair value	402,089			451,179
Fair value measured on recurring basis \| Fair Value \| 5.25% Senior Notes due 2025 \| Level 2
Financial assets and liabilities at fair value
Term loans and senior notes, fair value	884,643			929,917
Fair value measured on recurring basis \| Fair Value \| 5.25% Senior Notes due 2027 \| Level 2
Financial assets and liabilities at fair value
Term loans and senior notes, fair value	$ 530,750			$ 550,000