Borrowings (Schedule Of Long-Term Debt) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Jan. 23, 2016	Jul. 25, 2015
Debt Instrument [Line Items]
Total	$ 24,400	$ 25,251
Unaccreted discount/issuance costs	(123)	(131)
Hedge accounting fair value adjustments	320	231
Total	24,597	25,351
Current portion of long-term debt	3,006	3,894
Long-term debt	$ 21,591	$ 21,457
Floating Rate Notes 3-month Libor Plus 0.05% Due September 2015 [Member]
Debt Instrument [Line Items]
Maturity Date	Sep. 03, 2015	Sep. 03, 2015
Notes	$ 0	$ 850
Three-month LIBOR plus this Percentage (in %)	0.00%	0.05%
Effective Rate	0.00%	0.43%
Floating Rate Notes 3-month Libor Plus 0.28% Due March 2017
Debt Instrument [Line Items]
Maturity Date	Mar. 03, 2017	Mar. 03, 2017
Notes	$ 1,000	$ 1,000
Three-month LIBOR plus this Percentage (in %)	0.28%	0.28%
Effective Rate	0.77%	0.63%
Floating Rate Notes 3-month Libor Plus 0.31% Due June 2018
Debt Instrument [Line Items]
Maturity Date	Jun. 15, 2018	Jun. 15, 2018
Notes	$ 900	$ 900
Three-month LIBOR plus this Percentage (in %)	0.31%	0.31%
Effective Rate	0.89%	0.65%
Floating rate notes 3-month Libor plus 0.50% due March 2019
Debt Instrument [Line Items]
Maturity Date	Mar. 01, 2019	Mar. 01, 2019
Notes	$ 500	$ 500
Three-month LIBOR plus this Percentage (in %)	0.50%	0.50%
Effective Rate	0.97%	0.84%
Fixed-Rate Notes, 5.5%, Due February 2016
Debt Instrument [Line Items]
Maturity Date	Feb. 22, 2016	Feb. 22, 2016
Notes	$ 3,000	$ 3,000
Debt Instrument, Interest Rate, Stated Percentage	5.50%	5.50%
Effective Rate	3.12%	3.07%
Fixed-Rate Notes, 1.1%, Due March 2017
Debt Instrument [Line Items]
Maturity Date	Mar. 03, 2017	Mar. 03, 2017
Notes	$ 2,400	$ 2,400
Debt Instrument, Interest Rate, Stated Percentage	1.10%	1.10%
Effective Rate	0.83%	0.59%
Fixed-Rate Notes, 3.15%, Due March 2017
Debt Instrument [Line Items]
Maturity Date	Mar. 14, 2017	Mar. 14, 2017
Notes	$ 750	$ 750
Debt Instrument, Interest Rate, Stated Percentage	3.15%	3.15%
Effective Rate	1.07%	0.85%
Fixed rate notes 1.65% due June 2018
Debt Instrument [Line Items]
Maturity Date	Jun. 15, 2018	Jun. 15, 2018
Notes	$ 1,600	$ 1,600
Debt Instrument, Interest Rate, Stated Percentage	1.65%	1.65%
Effective Rate	1.72%	1.72%
Fixed-Rate Notes, 4.95%, Due February 2019
Debt Instrument [Line Items]
Maturity Date	Feb. 15, 2019	Feb. 15, 2019
Notes	$ 2,000	$ 2,000
Debt Instrument, Interest Rate, Stated Percentage	4.95%	4.95%
Effective Rate	4.76%	4.70%
Fixed-Rate Notes, 2.125%, Due March 2019
Debt Instrument [Line Items]
Maturity Date	Mar. 01, 2019	Mar. 01, 2019
Notes	$ 1,750	$ 1,750
Debt Instrument, Interest Rate, Stated Percentage	2.125%	2.125%
Effective Rate	1.04%	0.80%
Fixed-Rate Notes, 4.45%, Due January 2020
Debt Instrument [Line Items]
Maturity Date	Jan. 15, 2020	Jan. 15, 2020
Notes	$ 2,500	$ 2,500
Debt Instrument, Interest Rate, Stated Percentage	4.45%	4.45%
Effective Rate	3.20%	3.01%
Fixed-Rate Notes, 2.45%, Due June 2020
Debt Instrument [Line Items]
Maturity Date	Jun. 15, 2020	Jun. 15, 2020
Notes	$ 1,500	$ 1,500
Debt Instrument, Interest Rate, Stated Percentage	2.45%	2.45%
Effective Rate	2.54%	2.54%
Fixed-Rate Notes, 2.90%, Due March 2021
Debt Instrument [Line Items]
Maturity Date	Mar. 04, 2021	Mar. 04, 2021
Notes	$ 500	$ 500
Debt Instrument, Interest Rate, Stated Percentage	2.90%	2.90%
Effective Rate	1.20%	0.96%
Fixed-Rate Notes, 3.0 %, Due June 15, 2022 [Member]
Debt Instrument [Line Items]
Maturity Date	Jun. 15, 2022	Jun. 15, 2022
Notes	$ 500	$ 500
Debt Instrument, Interest Rate, Stated Percentage	3.00%	3.00%
Effective Rate	1.45%	1.21%
Fixed-Rate Notes,3.625%, Due March 2024
Debt Instrument [Line Items]
Maturity Date	Mar. 04, 2024	Mar. 04, 2024
Notes	$ 1,000	$ 1,000
Debt Instrument, Interest Rate, Stated Percentage	3.625%	3.625%
Effective Rate	1.32%	1.08%
Fixed-Rate Notes,3.5%, Due June 15, 2025 [Member]
Debt Instrument [Line Items]
Maturity Date	Jun. 15, 2025	Jun. 15, 2025
Notes	$ 500	$ 500
Debt Instrument, Interest Rate, Stated Percentage	3.50%	3.50%
Effective Rate	1.61%	1.37%
Fixed-Rate Notes, 5.9%, Due February 2039
Debt Instrument [Line Items]
Maturity Date	Feb. 15, 2039	Feb. 15, 2039
Notes	$ 2,000	$ 2,000
Debt Instrument, Interest Rate, Stated Percentage	5.90%	5.90%
Effective Rate	6.11%	6.11%
Fixed-Rate Notes, 5.5%, Due January 2040
Debt Instrument [Line Items]
Maturity Date	Jan. 15, 2040	Jan. 15, 2040
Notes	$ 2,000	$ 2,000
Debt Instrument, Interest Rate, Stated Percentage	5.50%	5.50%
Effective Rate	5.67%	5.67%
Other long-term debt
Debt Instrument [Line Items]
Other long-term debt	$ 0	$ 1
Effective Rate		2.08%

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