Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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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

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Fair Value of Financial Instruments - Auction rate securities (Details) - Auction rate securities - Significant Unobservable Inputs (Level 3) $ in Thousands	Sep. 28, 2019 USD ($) item Y	Jun. 29, 2019 USD ($)	Dec. 29, 2018 USD ($)
Weighted Average \| Estimated yield \| Discounted cash flow
Quantitative information for Level 3 Fair Value Measurements Assets
Unobservable Input	0.0359
Weighted Average \| Expected holding period \| Discounted cash flow
Quantitative information for Level 3 Fair Value Measurements Assets
Unobservable Input \| Y	10
Weighted Average \| Estimated discount rate \| Discounted cash flow
Quantitative information for Level 3 Fair Value Measurements Assets
Unobservable Input	0.0267
Recurring
Quantitative information for Level 3 Fair Value Measurements Assets
Fair value balance at the end of the period \| $	$ 5,715	$ 5,647	$ 5,759