Goodwill and Purchased Intangible Assets (Schedule of Intangible Assets Acquired Through Business Combinations) (Details) $ in Millions	9 Months Ended
	Apr. 27, 2019 USD ($) acquisition
Intangible Assets Acquired Through Business Combinations
Total, Amount	$ 672
Number of business combinations (acquisition) | acquisition	5
IPR&D
Intangible Assets Acquired Through Business Combinations
Indefinite Lives, Amount	$ 333
TECHNOLOGY
Intangible Assets Acquired Through Business Combinations
Finite Lives, Amount	166
CUSTOMER RELATIONSHIPS
Intangible Assets Acquired Through Business Combinations
Finite Lives, Amount	152
OTHER
Intangible Assets Acquired Through Business Combinations
Finite Lives, Amount	21
Duo
Intangible Assets Acquired Through Business Combinations
Total, Amount	342
Duo | IPR&D
Intangible Assets Acquired Through Business Combinations
Indefinite Lives, Amount	$ 77
Duo | TECHNOLOGY
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	5 years
Finite Lives, Amount	$ 153
Duo | CUSTOMER RELATIONSHIPS
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	5 years
Finite Lives, Amount	$ 94
Duo | OTHER
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	2 years 6 months
Finite Lives, Amount	$ 18
Luxtera
Intangible Assets Acquired Through Business Combinations
Total, Amount	319
Luxtera | IPR&D
Intangible Assets Acquired Through Business Combinations
Indefinite Lives, Amount	$ 256
Luxtera | TECHNOLOGY
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	4 years
Finite Lives, Amount	$ 2
Luxtera | CUSTOMER RELATIONSHIPS
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	5 years
Finite Lives, Amount	$ 58
Luxtera | OTHER
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	1 year 7 months 6 days
Finite Lives, Amount	$ 3
Others (three in total)
Intangible Assets Acquired Through Business Combinations
Total, Amount	$ 11
Number of business combinations (acquisition) | acquisition	3
Others (three in total) | IPR&D
Intangible Assets Acquired Through Business Combinations
Indefinite Lives, Amount	$ 0
Others (three in total) | TECHNOLOGY
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	4 years 4 months 24 days
Finite Lives, Amount	$ 11
Others (three in total) | CUSTOMER RELATIONSHIPS
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	0 years
Finite Lives, Amount	$ 0
Others (three in total) | OTHER
Intangible Assets Acquired Through Business Combinations
Weighted- Average Useful Life (in Years)	0 years
Finite Lives, Amount	$ 0