Investments and Fair Value Measurements - Narrative (Details)					2 Months Ended	3 Months Ended				9 Months Ended
	Sep. 20, 2020 USD ($)	Jan. 02, 2020 USD ($)	Apr. 25, 2019 USD ($)	Nov. 01, 2018 USD ($) $ / shares	Mar. 02, 2020 USD ($)	Sep. 27, 2020 USD ($)	Mar. 29, 2020 USD ($)	Dec. 29, 2019 USD ($)	Sep. 29, 2019 USD ($)	Sep. 27, 2020 USD ($) fund	Sep. 29, 2019 USD ($)	Jul. 31, 2015
Schedule of Investments [Line Items]
Marketable equity securities						$ 234,000,000		$ 106,000,000		$ 234,000,000
Marketable equity securities unrealized losses and gains						59,000,000			$ 47,000,000	128,000,000	$ 57,000,000
Strategic equity investments, without readily determinable fair values						305,000,000		220,000,000		$ 305,000,000
Number of venture capital investment funds | fund										2
Equity method investments						90,000,000		53,000,000		$ 90,000,000
Gains on deconsolidation											54,000,000
Loss on derivative assets related to terminated acquisition										(116,000,000)
Bridge Loan
Schedule of Investments [Line Items]
Principal amount of notes outstanding	$ 1,000,000,000
Investee
Schedule of Investments [Line Items]
Revenue from transactions with strategic investees						16,000,000			15,000,000	39,000,000	49,000,000
Venture Capital Investment Fund (the Fund)
Schedule of Investments [Line Items]
Commitment in new venture capital investment fund						100,000,000				100,000,000
Remaining capital commitment						40,000,000				40,000,000
Second Venture Capital Investment Fund
Schedule of Investments [Line Items]
Commitment in new venture capital investment fund						160,000,000				160,000,000
Remaining capital commitment						143,000,000				143,000,000
Helix Holdings I, LLC
Schedule of Investments [Line Items]
Contingent value right, terms			7 years
Gains on deconsolidation			$ 39,000,000
Contingent value right			$ 30,000,000
Unrealized gain (loss) from contingent value right									$ 2,000,000	5,000,000	$ (1,000,000)
Helix Holdings I, LLC | Variable Interest Entity, Primary Beneficiary
Schedule of Investments [Line Items]
Absorbed Helix's losses percentage											50.00%
Pacific Biosciences of California, Inc (PacBio)
Schedule of Investments [Line Items]
Cash payments				$ 1,200,000,000	$ 34,000,000		$ 132,000,000	18,000,000
Loss on contract termination		$ 98,000,000
Share price (in dollars per share) | $ / shares				$ 8.00
Business combination, contingent consideration arrangements, maximum outcome		52,000,000
Equity or debt financing to be raised		$ 100,000,000
Derivative asset						40,000,000				40,000,000
GRAIL Inc
Schedule of Investments [Line Items]
Net Assets						250,000,000		$ 190,000,000		250,000,000
Payments to acquire additional investment in security										60,000,000
Contingent value right, terms	12 years
Merger agreement consideration	$ 8,000,000,000
Cash payments	3,500,000,000
Business combination, equity Interests Issued and Issuable (in shares)	4,500,000,000
Capital raised	1,000,000,000
Business Combination, continuation payments	35,000,000
Business combination, threshold of continuation payments	315,000,000
Termination fee	300,000,000
Investment to be made if merger does not occur	$ 300,000,000
GRAIL Inc | Payment Rights Of One Billion, Each Twelve Years
Schedule of Investments [Line Items]
Contingent payment rights, first percentage	2.50%
Business Acquisition, Contingent Value Rights, Revenue Threshold	$ 1,000,000,000
GRAIL Inc | Payment Rights Of Above One Billion, Each Twelve Years
Schedule of Investments [Line Items]
Contingent payment rights, second percentage	9.00%
Business Acquisition, Contingent Value Rights, Revenue Threshold	$ 1,000,000,000
Helix Holdings I, LLC | Variable Interest Entity, Primary Beneficiary
Schedule of Investments [Line Items]
Equity ownership interest percentage												50.00%
Selling, General and Administrative | Pacific Biosciences of California, Inc (PacBio)
Schedule of Investments [Line Items]
Loss on derivative assets related to terminated acquisition										(92,000,000)
Other Operating Income (Expense) | Pacific Biosciences of California, Inc (PacBio)
Schedule of Investments [Line Items]
Loss on derivative assets related to terminated acquisition						$ (10,000,000)				$ (25,000,000)