Percentage of common stock issued to settle performance based restricted stock units of target shares granted.

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Share based compensation arrangement by share based payment award extended expiration period.

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Share based compensation arrangement by share based payment award vesting period description.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The cash outflow to reacquire common stock during the period.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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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Number of options outstanding, including both vested and non-vested options.

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Stockholders' Equity - Additional Information (Detail) - USD ($)		3 Months Ended		6 Months Ended		198 Months Ended
	Nov. 13, 2019	Oct. 25, 2019	Oct. 26, 2018	Oct. 25, 2019	Oct. 26, 2018	Oct. 25, 2019	Apr. 26, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense related to equity awards		$ 339,000,000		$ 339,000,000		$ 339,000,000
Unrecognized compensation expense will be amortized on a straight-line basis over a weighted-average remaining period, in years				2 years 3 months 18 days
Stock repurchase program, authorized amount		13,600,000,000		$ 13,600,000,000		$ 13,600,000,000
Allocation of purchase price of share repurchases		$ 500,000,000	$ 561,000,000	$ 750,000,000	$ 1,061,000,000
Repurchase of common stock, shares				14,000,000		327,000,000
Average price of common stock repurchased under repurchase program				$ 55.06		$ 38.20
Aggregate purchase price of common stock authorized under repurchase program				$ 750,000,000	$ 1,061,000,000	$ 12,500,000,000
Cash dividends declared, per common share		$ 0.48	$ 0.40	$ 0.96	$ 0.80
Other income, net
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Realized gains from sale of available-for-sale securities				$ 14,000,000
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash dividends declared, per common share	$ 0.48
Cash dividend payable date	Jan. 22, 2020
Cash dividend record date	Jan. 03, 2020
Additional Paid-in Capital
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocation of purchase price of share repurchases				398,000,000
Retained Earnings (Accumulated Deficit)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocation of purchase price of share repurchases		$ 243,000,000	$ 241,000,000	$ 352,000,000	$ 464,000,000
Performance Based Restricted Stock Unit
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
RSUs grant date fair value		$ 18,000,000		$ 18,000,000		$ 18,000,000
Vesting period, description				For the remaining PBRSUs granted, the number of shares issued will depend upon our achievement against a cumulative Adjusted Operating Income (AOI) target, as defined in the grant agreements, for the three year period from fiscal 2020 through 2022.
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of Common stock issued to settle PBRSUs of target shares granted				0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of options outstanding		1,000,000		1,000,000		1,000,000	1,000,000
Percentage of Common stock issued to settle PBRSUs of target shares granted				200.00%
1999 Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation arrangement by share based payment award extended expiration period		10 years