Comprehensive Income (Reclassification out of other comprehensive income) (Details) - USD ($) $ in Millions	12 Months Ended
	Jul. 30, 2016	Jul. 25, 2015	Jul. 26, 2014
Net Unrealized Gains on Available-for-Sale Investments | Other income (loss), net
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Net unrealized gains on available-for-sale investments	$ (1)	$ 157	$ 300
Cash Flow Hedges
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Total amounts reclassified out of AOCI	(20)	(154)	68
Cash Flow Hedges | Operating expenses
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Total amounts reclassified out of AOCI	(15)	(121)	55
Cash Flow Hedges | Cost of sales—service
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Total amounts reclassified out of AOCI	(5)	(33)	13
Cumulative translation adjustment and Actuarial gains and losses | Operating expenses
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Total amounts reclassified out of AOCI	6	(2)	0
Total Cisco Shareholders’ Equity
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Total amounts reclassified out of AOCI	$ (15)	$ 1	$ 368