Debt - Components of Convertible Senior Notes (Details) - USD ($) $ in Thousands	Dec. 28, 2019	Dec. 29, 2018	Sep. 29, 2018
Debt Instrument [Line Items]
Net carrying amount	$ 323,678	$ 266,929
2.125% Convertible Senior Notes Due September 1, 2024
Debt Instrument [Line Items]
Principal	402,500	402,500	$ 1
Unamortized discount	(109,652)	(127,264)
Unamortized issuance cost	(7,158)	(8,307)
Net carrying amount	$ 285,690	$ 266,929

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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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.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

+ 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

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
-Section S99
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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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