Financing - Additional Information (Detail) - USD ($)	1 Months Ended	8 Months Ended
Apr. 18, 2019	May 04, 2019	Aug. 25, 2018
Debt Instrument [Line Items]
Remaining borrowing capacity under revolving credit facility		$ 1,997,000,000
Amount available under credit facility		2,000,000,000
Fair value of the Company's debt		5,190,000,000	$ 4,948,000,000
Excess (shortfall) of fair value of debt over (from) carrying value		37,900,000	57,500,000
Third Amended and Restated Credit Agreement [Member]
Debt Instrument [Line Items]
Amount available under credit facility		1,600,000,000
Master Extension Agreement [Member]
Debt Instrument [Line Items]
Amount available under credit facility		2,000,000,000
Revolving credit agreement, available additional borrowing capacity		400,000,000
Maximum amount available under credit facility		$ 2,400,000,000
Credit facility expiration date		Nov. 18, 2022
Credit Agreement description		Under the Revolving Credit Agreement, the Company may borrow funds consisting of Eurodollar loans, base rate loans or a combination of both. Interest accrues on Eurodollar loans at a defined Eurodollar rate, defined as LIBOR plus the applicable percentage, as defined in the Revolving Credit Agreement, depending upon the Company’s senior, unsecured, (non-credit enhanced) long-term debt ratings. Interest accrues on base rate loans as defined in the Revolving Credit Agreement.
Extended expiration of credit facility		1 year
Letters of credit, outstanding		$ 3,300,000
1.625% Senior Notes due April 2019, effective interest rate of 1.77% [Member]
Debt Instrument [Line Items]
Long-term debt	$ 250,000,000	$ 0	250,000,000
Stated interest rate percentage	1.625%	1.625%
Debt instrument maturity, month and year	2019-04	2019-04
3.125% Senior Notes due April 2024, effective interest rate 3.32% [Member]
Debt Instrument [Line Items]
Long-term debt	$ 300,000,000	$ 300,000,000
Stated interest rate percentage	3.125%	3.125%
Debt instrument maturity, month and year	2024-04	2024-04
3.750% Senior Notes due April 2029, effective interest rate of 3.86% [Member]
Debt Instrument [Line Items]
Long-term debt	$ 450,000,000	$ 450,000,000
Stated interest rate percentage	3.75%	3.75%
Debt instrument maturity, month and year	2029-04	2029-04

Maturity date (by month and year) for debt instrument.

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- Definition

Line Of Credit Facility Additional Available Borrowing Capacity

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No definition available.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

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

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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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No definition available.

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This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of long-term debt instruments that have contractual principal amounts and for which the fair value option has been elected.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Description of the terms of a credit facility arrangement. Terms typically include interest rate, collateral required, guarantees required, repayment requirements, and restrictions on use of assets and activities of the entity.

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Date the credit facility terminates, in CCYY-MM-DD format.

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Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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