Financing Arrangements , Long-term Debt (Details) - USD ($)		12 Months Ended
	Jan. 26, 2015	Apr. 24, 2015	Dec. 10, 2014	Apr. 25, 2014	Feb. 28, 2014
Debt Instrument [Line Items]
Deferred gains from interest rate swap terminations, net		$ (3,000,000)		$ (20,000,000)
Discount		(499,000,000)		25,000,000
Total Long-Term Debt		$ 33,752,000,000		10,315,000,000
Senior Unsecured Term Loan Credit Agreement
Debt Instrument [Line Items]
Proceeds from Lines of Credit	$ 3,000,000,000.000
Debt term	3 years
Senior notes | 4.750 percent ten-year 2005 senior notes
Debt Instrument [Line Items]
Stated interest rate		4.75%
Debt term		10 years
Long-term Debt		$ 0		$ 600,000,000
Effective Interest Rate		0.00%		4.76%
Senior notes | 2.625 percent five-year 2011 senior notes
Debt Instrument [Line Items]
Stated interest rate		2.625%
Debt term		5 years
Long-term Debt		$ 0		$ 500,000,000
Effective Interest Rate		0.00%		2.72%
Senior notes | Floating rate three-year 2014 senior notes
Debt Instrument [Line Items]
Debt term		3 years
Long-term Debt		$ 250,000,000		$ 250,000,000
Effective Interest Rate		0.32%		0.32%
Senior notes | 0.875 percent three-year 2014 senior notes
Debt Instrument [Line Items]
Stated interest rate		0.875%			0.875%
Debt term		3 years
Long-term Debt		$ 250,000,000		$ 250,000,000
Effective Interest Rate		0.91%		0.91%
Senior notes | 6.000 percent ten-year 2008 CIFSA senior notes
Debt Instrument [Line Items]
Stated interest rate		6.00%
Debt term		10 years
Long-term Debt		$ 1,150,000,000		$ 0
Effective Interest Rate		1.41%		0.00%
Senior notes | 1.375 percent five-year 2013 senior notes
Debt Instrument [Line Items]
Stated interest rate		1.375%
Debt term		5 years
Long-term Debt		$ 1,000,000,000		$ 1,000,000,000
Effective Interest Rate		1.41%		1.41%
Senior notes | 1.500 percent three-year 2015 senior notes
Debt Instrument [Line Items]
Stated interest rate		1.50%	1.50%
Debt term		3 years
Long-term Debt		$ 1,000,000,000		$ 0
Effective Interest Rate		1.59%		0.00%
Senior notes | 5.600 percent ten-year 2009 senior notes
Debt Instrument [Line Items]
Stated interest rate		5.60%
Debt term		10 years
Long-term Debt		$ 400,000,000		$ 400,000,000
Effective Interest Rate		5.61%		5.61%
Senior notes | 4.450 percent ten-year 2010 senior notes
Debt Instrument [Line Items]
Stated interest rate		4.45%
Debt term		10 years
Long-term Debt		$ 1,250,000,000		$ 1,250,000,000
Effective Interest Rate		4.47%		4.47%
Senior notes | 4.200 percent ten-year 2010 CIFSA senior notes
Debt Instrument [Line Items]
Stated interest rate		4.20%
Debt term		10 years
Long-term Debt		$ 600,000,000		$ 0
Effective Interest Rate		2.22%		0.00%
Senior notes | 2.500 percent five-year 2015 senior notes
Debt Instrument [Line Items]
Stated interest rate		2.50%	2.50%
Debt term		5 years
Long-term Debt		$ 2,500,000,000		$ 0
Effective Interest Rate		2.52%		0.00%
Senior notes | Floating rate five-year 2015 senior notes
Debt Instrument [Line Items]
Debt term		5 years
Long-term Debt		$ 500,000,000		$ 0
Effective Interest Rate		1.04%		0.00%
Senior notes | 4.125 percent ten-year 2011 senior notes
Debt Instrument [Line Items]
Stated interest rate		4.125%
Debt term		10 years
Long-term Debt		$ 500,000,000		$ 500,000,000
Effective Interest Rate		4.19%		4.19%
Senior notes | 3.125 percent ten-year 2012 senior notes
Debt Instrument [Line Items]
Stated interest rate		3.125%
Debt term		10 years
Long-term Debt		$ 675,000,000		$ 675,000,000
Effective Interest Rate		3.16%		3.16%
Senior notes | 3.200 percent ten-year 2012 CIFSA senior notes
Debt Instrument [Line Items]
Stated interest rate		3.20%
Debt term		10 years
Long-term Debt		$ 650,000,000		$ 0
Effective Interest Rate		2.66%		0.00%
Senior notes | 3.150 percent seven-year 2015 senior notes
Debt Instrument [Line Items]
Stated interest rate		3.15%	3.15%
Debt term		7 years
Long-term Debt		$ 2,500,000,000		$ 0
Effective Interest Rate		3.18%		0.00%
Senior notes | 2.750 percent ten-year 2013 senior notes
Debt Instrument [Line Items]
Stated interest rate		2.75%
Debt term		10 years
Long-term Debt		$ 1,250,000,000		$ 1,250,000,000
Effective Interest Rate		2.78%		2.78%
Senior notes | 2.950 percent ten-year 2013 CIFSA senior notes
Debt Instrument [Line Items]
Stated interest rate		2.95%
Debt term		10 years
Long-term Debt		$ 750,000,000		$ 0
Effective Interest Rate		2.67%		0.00%
Senior notes | 3.625 percent ten-year 2014 senior notes
Debt Instrument [Line Items]
Stated interest rate		3.625%			3.625%
Debt term		10 years
Long-term Debt		$ 850,000,000		$ 850,000,000
Effective Interest Rate		3.65%		3.65%
Senior notes | 3.500 percent ten-year 2015 senior notes
Debt Instrument [Line Items]
Stated interest rate		3.50%	3.50%
Debt term		10 years
Long-term Debt		$ 4,000,000,000		$ 0
Effective Interest Rate		3.61%		0.00%
Senior notes | 4.375 percent twenty-year 2015 senior notes
Debt Instrument [Line Items]
Stated interest rate		4.375%	4.375%
Debt term		20 years
Long-term Debt		$ 2,500,000,000		$ 0
Effective Interest Rate		4.44%		0.00%
Senior notes | 6.550 percent thirty-year 2007 CIFSA senior notes
Debt Instrument [Line Items]
Stated interest rate		6.55%
Debt term		30 years
Long-term Debt		$ 850,000,000		$ 0
Effective Interest Rate		3.75%		0.00%
Senior notes | 6.500 percent thirty-year 2009 senior notes
Debt Instrument [Line Items]
Stated interest rate		6.50%
Debt term		30 years
Long-term Debt		$ 300,000,000		$ 300,000,000
Effective Interest Rate		6.52%		6.52%
Senior notes | 5.550 percent thirty-year 2010 senior notes
Debt Instrument [Line Items]
Stated interest rate		5.55%
Debt term		30 years
Long-term Debt		$ 500,000,000		$ 500,000,000
Effective Interest Rate		5.56%		5.56%
Senior notes | 4.500 percent thirty-year 2012 senior notes
Debt Instrument [Line Items]
Stated interest rate		4.50%
Debt term		30 years
Long-term Debt		$ 400,000,000		$ 400,000,000
Effective Interest Rate		4.51%		4.51%
Senior notes | 4.000 percent thirty-year 2013 senior notes
Debt Instrument [Line Items]
Stated interest rate		4.00%
Debt term		30 years
Long-term Debt		$ 750,000,000		$ 750,000,000
Effective Interest Rate		4.12%		4.12%
Senior notes | 4.625 percent thirty-year 2014 senior notes
Debt Instrument [Line Items]
Stated interest rate		4.625%			4.625%
Debt term		30 years
Long-term Debt		$ 650,000,000		$ 650,000,000
Effective Interest Rate		4.67%		4.67%
Senior notes | 4.625 thirty-year 2015 senior notes
Debt Instrument [Line Items]
Stated interest rate		4.625%	4.625%
Debt term		30 years
Long-term Debt		$ 4,000,000,000		$ 0
Effective Interest Rate		4.64%		0.00%
Senior notes | Three-year term loan
Debt Instrument [Line Items]
Debt term		3 years
Long-term Debt		$ 3,000,000,000		$ 0
Effective Interest Rate		1.12%		0.00%
Interest rate swaps
Debt Instrument [Line Items]
Long-term Debt		$ 79,000,000		$ 56,000,000
Capital lease obligations
Debt Instrument [Line Items]
Capital lease obligations		$ 129,000,000		$ 139,000,000
Effective Interest Rate		3.52%		3.62%
Bank borrowings
Debt Instrument [Line Items]
Long-term Debt		$ 17,000,000		$ 0