Comprehensive Income (AOCI components) (Details) - USD ($) $ in Millions	3 Months Ended
	Oct. 24, 2015	Oct. 25, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI Balance	$ 61
AOCI Balance	(252)
Net Unrealized Gains on Available-for-Sale Investments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI Balance	310	$ 424
Other comprehensive income (loss) before reclassifications attributable to Cisco Systems, Inc.	(155)	(36)
(Gains) losses reclassified out of AOCI	1	(7)
Tax benefit (expense)	56	16
AOCI Balance	212	397
Net Unrealized Losses Cash Flow Hedging Instruments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI Balance	(16)	(12)
Other comprehensive income (loss) before reclassifications attributable to Cisco Systems, Inc.	(4)	(56)
(Gains) losses reclassified out of AOCI	3	4
Tax benefit (expense)	2	3
AOCI Balance	(15)	(61)
Cumulative Translation Adjustment and Actuarial Gains and Losses
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI Balance	(233)	265
Other comprehensive income (loss) before reclassifications attributable to Cisco Systems, Inc.	(178)	(161)
(Gains) losses reclassified out of AOCI	1	0
Tax benefit (expense)	(39)	11
AOCI Balance	(449)	115
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
AOCI Balance	61	677
Other comprehensive income (loss) before reclassifications attributable to Cisco Systems, Inc.	(337)	(253)
(Gains) losses reclassified out of AOCI	5	(3)
Tax benefit (expense)	19	30
AOCI Balance	$ (252)	$ 451