Borrowings (Schedule of Long-Term Debt) (Parenthetical) (Details)	12 Months Ended
	Jul. 27, 2013
Floating-rate notes, due 2014
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Mar. 14, 2014
1.625% fixed-rate notes, due 2014
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Mar. 14, 2014
Fixed interest rate	1.625%
2.90% fixed-rate notes, due 2014
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Nov. 17, 2014
Fixed interest rate	2.90%
5.50% fixed-rate notes, due 2016
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Feb. 22, 2016
Fixed interest rate	5.50%
3.15% fixed-rate notes, due 2017
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Mar. 14, 2017
Fixed interest rate	3.15%
4.95% fixed-rate notes, due 2019
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Feb. 15, 2019
Fixed interest rate	4.95%
4.45% fixed-rate notes, due 2020
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jan. 15, 2020
Fixed interest rate	4.45%
5.90% fixed-rate notes, due 2039
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Feb. 15, 2039
Fixed interest rate	5.90%
5.50% fixed-rate notes, due 2040
Debt Instrument [Line Items]
Debt Instrument, Maturity Date	Jan. 15, 2040
Fixed interest rate	5.50%