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Goodwill, Amount that Exceeds Carrying Value

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Goodwill Impairment, Discounted cash flow model, Discount rate

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Loss Contingency, License Granted Intangible Assets

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of fair value of reporting unit in excess of carrying amount.

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Supplemental Balance Sheet Details - Intangible Assets and Goodwill Narrative (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Oct. 02, 2022	Jul. 03, 2022	Oct. 03, 2021	Oct. 02, 2022	Oct. 03, 2021	Jan. 02, 2022
Indefinite-lived Intangible Assets [Line Items]
Measurement period adjustment				$ (6)
Goodwill impairment	$ 3,914		$ 0	3,914	$ 0
Goodwill	3,238			3,238		$ 7,113
GRAIL
Indefinite-lived Intangible Assets [Line Items]
Measurement period adjustment	(6)
Deferred tax assets	$ 6
Fair value of discount rate (as a percent)	22.00%	16.00%
Amount exceeding carrying value		$ 700
Goodwill impairment	$ 3,914	0
Goodwill	2,178			2,178
Core Illumina
Indefinite-lived Intangible Assets [Line Items]
Fair value in excess of carrying amount (more than)	30,000			$ 30,000
Developed technology
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired		$ 23
Useful life (in years)		7 years
Database
Indefinite-lived Intangible Assets [Line Items]
Finite-lived intangible assets acquired		$ 12
Useful life (in years)		7 years
License \| Complete Genomics
Indefinite-lived Intangible Assets [Line Items]
Loss contingency, license granted	$ 180
Amortization period (in years)	6 years 6 months