Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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-Article 12
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Market value related to the hedged item in an interest rate fair value hedge, offset by the gain (loss) on the hedging instrument to the extent that the fair value hedge is determined to be effective.

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Amount of unrealized gain (loss), net of tax as of the balance sheet date, related to the increase or decrease in fair value of interest rate derivatives designated as cash flow hedging instruments, which was recorded in accumulated other comprehensive income to the extent that the cash flow hedge was determined to be effective.

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No definition available.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Average fixed interest rate related to the group of interest rate derivatives.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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Amount of net gain (loss) recognized in earnings when a hedged firm commitment no longer qualifies as a fair value hedge.

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-Name Accounting Standards Codification
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The net gain (loss) during the reporting period due to ineffectiveness in foreign currency cash flow hedges. Recognized in earnings.

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The net gain (loss) during the reporting period due to ineffectiveness in interest rate cash flow hedges. Recognized in earnings.

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The net gain (loss) recognized in earnings during the period due to the ineffectiveness on interest rate fair value hedges.

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Maximum amount of time remaining before foreign currency exchange rate derivatives mature or expire, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Derivatives and Currency Exchange Risk Management - Narrative (Details) - USD ($)	3 Months Ended
	Jul. 28, 2017	Jul. 29, 2016	Apr. 28, 2017	Jan. 27, 2017
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gains (losses) relating to ineffectiveness of cash flow hedges	$ 0	$ 0
Gains (losses) relating to ineffectiveness of forward starting interest rate derivatives		0
After-tax net unrealized gains (losses) associated with cash flow hedging instruments recorded in AOCI	(134,000,000)		$ 37,000,000
Cash flow hedge unrealized losses to be reclassified over the next 12 months	37,000,000
Debt, face amount	28,900,000,000		28,900,000,000
Gains (losses) relating to ineffectiveness of interest rate fair value hedges	0	0
Gains (losses) on firm commitments that no longer qualify as fair value hedges	0	0
Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gains (losses) recognized in AOCI	(250,000,000)	121,000,000
Effective portion of net gains (losses) on derivative instruments reclassified from accumulated other comprehensive loss	22,000,000	15,000,000
Currency exchange rate contracts
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	11,800,000,000		10,800,000,000
Currency exchange rate contracts \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gains (losses) recognized in AOCI	(250,000,000)	121,000,000
Currency exchange rate contracts \| Derivatives not designated as hedging instruments
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	5,400,000,000		4,900,000,000
Currency exchange rate contracts \| Derivatives designated as hedging instruments \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	$ 6,300,000,000		5,800,000,000
Maximum remaining maturity of foreign currency derivatives	3 years
Interest rate swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gains (losses) recognized in AOCI		(23,000,000)
Interest rate swaps \| Cash flow hedging \| Interest expense, net
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Effective portion of net gains (losses) on derivative instruments reclassified from accumulated other comprehensive loss	$ 0	$ 0
Interest rate swaps \| Derivatives designated as hedging instruments \| Cash flow hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount				$ 300,000,000
Average interest rate				3.10%
Interest rate swaps \| Derivatives designated as hedging instruments \| Fair value hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Derivative, notional amount	1,200,000,000		1,200,000,000
Market value of outstanding interest rate swap agreements - net unrealized gain	41,000,000		41,000,000
Market value of hedged item - net unrealized loss	$ 41,000,000		41,000,000
4.125 percent ten-year 2011 senior notes \| Senior notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Stated interest rate	4.125%
4.125 percent ten-year 2011 senior notes \| Senior notes \| Interest rate swaps \| Derivatives designated as hedging instruments \| Fair value hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Debt, face amount	$ 500,000,000		$ 500,000,000
Stated interest rate	4.125%		4.125%
3.125 percent ten-year 2012 senior notes \| Senior notes
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Stated interest rate	3.125%
3.125 percent ten-year 2012 senior notes \| Senior notes \| Interest rate swaps \| Derivatives designated as hedging instruments \| Fair value hedging
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Debt, face amount	$ 675,000,000		$ 675,000,000
Stated interest rate	3.125%		3.125%