Comprehensive Income (AOCI components) (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 25, 2015	Jul. 26, 2014	Jul. 27, 2013
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance - Beginning	$ 677
Balance - Ending	61	$ 677
Net Unrealized Gains on Available-for-Sale Investments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance - Beginning	424	379	$ 409
Other comprehensive income (loss) before reclassifications attributable to Cisco Systems, Inc.	(28)	380	3
(Gains) losses reclassified out of AOCI	(157)	(300)	(48)
Tax benefit (expense)	71	(35)	15
Balance - Ending	310	424	379
Net Unrealized Gains (Losses) Cash Flow Hedging Instruments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance - Beginning	(12)	8	(53)
Other comprehensive income (loss) before reclassifications attributable to Cisco Systems, Inc.	(159)	48	74
(Gains) losses reclassified out of AOCI	154	(68)	(12)
Tax benefit (expense)	1	0	(1)
Balance - Ending	(16)	(12)	8
Cumulative translation adjustment and Actuarial gains and losses
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance - Beginning	265	221	305
Other comprehensive income (loss) before reclassifications attributable to Cisco Systems, Inc.	(563)	49	(83)
(Gains) losses reclassified out of AOCI	2	0	0
Tax benefit (expense)	63	(5)	(1)
Balance - Ending	(233)	265	221
Parent [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance - Beginning	677	608	661
Other comprehensive income (loss) before reclassifications attributable to Cisco Systems, Inc.	(750)	477	(6)
(Gains) losses reclassified out of AOCI	(1)	(368)	(60)
Tax benefit (expense)	135	(40)	13
Balance - Ending	$ 61	$ 677	$ 608