Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

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-Paragraph 1
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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- Definition

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

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-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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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

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.

+ References

No definition available.

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Debt and Credit Sources - Schedule of Convertible Debt (Details) - USD ($)	Sep. 27, 2020	Dec. 29, 2019	Dec. 31, 2015	Dec. 28, 2014	Jun. 30, 2014
Debt Instrument [Line Items]
Face Value	$ 894,773,000	$ 986,244,000
0.875% debentures due 2021
Debt Instrument [Line Items]
Face Value					$ 400,000,000.0
Interest rate	0.875%				0.875%
4.00% debentures due 2023
Debt Instrument [Line Items]
Face Value			$ 425,000,000.0
Interest rate	4.00%		4.00%
Convertible Debt
Debt Instrument [Line Items]
Carrying Value	$ 723,390,000	820,259,000
Face Value	726,583,000	825,000,000
Fair value	697,918,000	719,668,000
Convertible Debt \| 0.875% debentures due 2021
Debt Instrument [Line Items]
Carrying Value	301,258,000	399,058,000
Face Value	301,583,000	400,000,000
Fair value	$ 296,794,000	371,040,000
Interest rate	0.875%			0.875%
Convertible Debt \| 4.00% debentures due 2023
Debt Instrument [Line Items]
Carrying Value	$ 422,132,000	421,201,000
Face Value	425,000,000	425,000,000
Fair value	$ 401,124,000	$ 348,628,000