Fair Value Measurements - Level 3 significant unobservable input sensitivity (Details) - Equity investments - Level 3 $ in Thousands	Jun. 28, 2020 USD ($)
Discounted cash flows
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Total assets	$ 9,776
Measurement Input, Default Rate \| Minimum \| Discounted cash flows
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.095
Measurement Input, Default Rate \| Minimum \| Valuation Technique, Residual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.075
Measurement Input, Default Rate \| Maximum \| Discounted cash flows
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.13
Measurement Input, Default Rate \| Maximum \| Valuation Technique, Residual
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input	0.0775

Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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Value of input used to measure investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

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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