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Financial Instruments and Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Oct. 04, 2019	Sep. 28, 2018	Oct. 04, 2019	Sep. 28, 2018	Mar. 29, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value of non-marketable equity investments	$ 186		$ 186		$ 184
Equity method investment	11		11		32
Loss from equity interest	11	$ 34	22	$ 60
Digicert Parent, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Equity method investment	11		11		32
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair value of debt	4,020		4,020		$ 3,964
Other expense, net \| Digicert Parent, Inc.
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loss from equity interest	$ 11	$ 34	$ 22	$ 60