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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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Gross amount of debt extinguished.

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No definition available.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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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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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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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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Long-Term Debt - Additional Information (Detail) - USD ($)	1 Months Ended				9 Months Ended
	Aug. 31, 2020	Jul. 31, 2020	Jun. 30, 2020	Apr. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Debt Disclosure [Abstract]
Interest paid, net of amounts capitalized					$ 234,000,000	$ 247,000,000
Maximum aggregate borrowings under credit facility (up to)					4,500,000,000
Proceeds from credit facility					4,500,000,000
Repayments of credit facility					3,600,000,000
Outstanding under credit facility					900,000,000		$ 0
Senior Notes
Short-term Debt [Line Items]
Debt purchased			$ 853,000,000
Series EE Notes, interest rate of 5.8%, face amount of $1,600, maturing May 1, 2025 (effective interest rate of 6.0%) \| Senior Notes
Short-term Debt [Line Items]
Aggregate principal amount				$ 1,600,000,000	$ 1,600,000,000
Interest rate				5.75%	5.80%
Net proceeds				$ 1,581,000,000
Series FF Notes, interest rate of 4.6%, face amount of $1,000, maturing June 15, 2030 (effective interest rate of 4.8%) \| Senior Notes
Short-term Debt [Line Items]
Aggregate principal amount			$ 1,000,000,000.0		$ 1,000,000,000
Interest rate			4.625%		4.60%
Net proceeds			$ 985,000,000
Series Q Notes, interest rate of 2.3%, face amount of $399, maturing January 15, 2022 (effective interest rate of 2.5%) \| Senior Notes
Short-term Debt [Line Items]
Aggregate principal amount					$ 399,000,000
Interest rate			2.30%		2.30%
Debt purchased			$ 351,000,000
Series L Notes, interest rate of 3.3%, face amount of $173, maturing September 15, 2022 (effective interest rate of 3.4%) \| Senior Notes
Short-term Debt [Line Items]
Aggregate principal amount					$ 173,000,000
Interest rate			3.30%		3.30%
Debt purchased			$ 176,000,000
Series DD Notes, interest rate of 2.1%, face amount of $224, maturing October 3, 2022 (effective interest rate of 1.2%) \| Senior Notes
Short-term Debt [Line Items]
Aggregate principal amount					$ 224,000,000
Interest rate			2.10%		2.10%
Debt purchased			$ 326,000,000
Series M Notes, interest rate of 3.4%, face amount of $350, matured October 15, 2020 (effective interest rate of 3.6%) \| Senior Notes
Short-term Debt [Line Items]
Aggregate principal amount					$ 350,000,000
Interest rate					3.40%
Debt purchased		$ 350,000,000
Series GG Notes, interest rate of 3.5%, face amount of $1,000, maturing October 15, 2032 (effective interest rate of 3.7%) \| Senior Notes
Short-term Debt [Line Items]
Aggregate principal amount	$ 1,000,000,000.0				$ 1,000,000,000
Interest rate	3.50%				3.50%
Net proceeds	$ 984,000,000