Face (par) amount of debt instrument at time of issuance.

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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount, after accumulated amortization, of debt discount (premium).

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- Definition

Fair value as of the balance sheet date of interest rate derivative assets, net of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized on the balance sheet.

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No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Indebtedness - Summary of Total Indebtedness (Detail) - USD ($)			3 Months Ended	6 Months Ended
	May 20, 2020	Mar. 25, 2020	Mar. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal Amount				$ 6,304,000,000	$ 5,603,000,000
Fair Value of Interest Rate Swap				87,000,000	27,000,000
Unamortized (Discount) Premium				(21,000,000)	(17,000,000)
Unamortized Debt Issuance Costs				(37,000,000)	(32,000,000)
Long term debt				$ 6,333,000,000	$ 5,581,000,000
4.50% 2012 Senior Notes, due 2022
Debt Instrument [Line Items]
Notes payable, interest rate				4.50%	4.50%
Principal Amount				$ 500,000,000	$ 500,000,000
Fair Value of Interest Rate Swap				18,000,000	9,000,000
Unamortized (Discount) Premium				(1,000,000)	(1,000,000)
Unamortized Debt Issuance Costs				(1,000,000)	(1,000,000)
Long term debt				$ 516,000,000	$ 507,000,000
4.875% 2013 Senior Notes, due 2024
Debt Instrument [Line Items]
Notes payable, interest rate				4.875%	4.875%
Principal Amount				$ 500,000,000	$ 500,000,000
Unamortized (Discount) Premium				(1,000,000)	(1,000,000)
Unamortized Debt Issuance Costs				(1,000,000)	(2,000,000)
Long term debt				$ 498,000,000	$ 497,000,000
5.25% 2014 Senior Notes (30-Year), due 2044
Debt Instrument [Line Items]
Notes payable, interest rate				5.25%	5.25%
Debt instrument, term			30 years	30 years
Principal Amount				$ 600,000,000	$ 600,000,000
Unamortized (Discount) Premium				4,000,000	4,000,000
Unamortized Debt Issuance Costs				(5,000,000)	(5,000,000)
Long term debt				$ 599,000,000	$ 599,000,000
1.75% 2015 Senior Notes, due 2027
Debt Instrument [Line Items]
Notes payable, interest rate				1.75%	1.75%
Principal Amount				$ 562,000,000	$ 561,000,000
Unamortized (Discount) Premium				0	0
Unamortized Debt Issuance Costs				(3,000,000)	(3,000,000)
Long term debt				$ 559,000,000	$ 558,000,000
2.75% 2017 Senior Notes, due 2021
Debt Instrument [Line Items]
Notes payable, interest rate				2.75%	2.75%
Principal Amount				$ 500,000,000	$ 500,000,000
Fair Value of Interest Rate Swap				19,000,000	11,000,000
Unamortized (Discount) Premium				0	(1,000,000)
Unamortized Debt Issuance Costs				(1,000,000)	(2,000,000)
Long term debt				$ 518,000,000	$ 508,000,000
2.625% 2017 Senior Notes, due 2023
Debt Instrument [Line Items]
Notes payable, interest rate				2.625%	2.625%
Principal Amount				$ 500,000,000	$ 500,000,000
Fair Value of Interest Rate Swap				15,000,000	7,000,000
Unamortized (Discount) Premium				(1,000,000)	(1,000,000)
Unamortized Debt Issuance Costs				(2,000,000)	(2,000,000)
Long term debt				$ 512,000,000	$ 504,000,000
3.25% 2017 Senior Notes, due 2028
Debt Instrument [Line Items]
Notes payable, interest rate				3.25%	3.25%
Principal Amount				$ 500,000,000	$ 500,000,000
Fair Value of Interest Rate Swap				35,000,000
Unamortized (Discount) Premium				(4,000,000)	(4,000,000)
Unamortized Debt Issuance Costs				(3,000,000)	(3,000,000)
Long term debt				$ 528,000,000	$ 493,000,000
3.25% 2018 Senior Notes, due 2021
Debt Instrument [Line Items]
Notes payable, interest rate				3.25%	3.25%
Principal Amount					$ 300,000,000
Unamortized (Discount) Premium					0
Unamortized Debt Issuance Costs					(1,000,000)
Long term debt					$ 299,000,000
4.25% 2018 Senior Notes, due 2029
Debt Instrument [Line Items]
Notes payable, interest rate				4.25%	4.25%
Principal Amount				$ 400,000,000	$ 400,000,000
Unamortized (Discount) Premium				(3,000,000)	(3,000,000)
Unamortized Debt Issuance Costs				(3,000,000)	(3,000,000)
Long term debt				$ 394,000,000	$ 394,000,000
4.875% 2018 Senior Notes, due 2048
Debt Instrument [Line Items]
Notes payable, interest rate				4.875%	4.875%
Principal Amount				$ 400,000,000	$ 400,000,000
Unamortized (Discount) Premium				(7,000,000)	(7,000,000)
Unamortized Debt Issuance Costs				(4,000,000)	(4,000,000)
Long term debt				$ 389,000,000	$ 389,000,000
0.950% Senior Notes Due 2030
Debt Instrument [Line Items]
Notes payable, interest rate				0.95%	0.95%
Principal Amount				$ 842,000,000	$ 842,000,000
Unamortized (Discount) Premium				(3,000,000)	(3,000,000)
Unamortized Debt Issuance Costs				(6,000,000)	(6,000,000)
Long term debt				$ 833,000,000	$ 833,000,000
3.75% 2020 Senior Notes, due 2025
Debt Instrument [Line Items]
Notes payable, interest rate		3.75%		3.75%
Debt instrument, term		5 years
Principal Amount		$ 700,000,000		$ 700,000,000
Unamortized (Discount) Premium				(1,000,000)
Unamortized Debt Issuance Costs				(5,000,000)
Long term debt				$ 694,000,000
3.25% 2020 Senior Notes, due 2050
Debt Instrument [Line Items]
Notes payable, interest rate	3.25%			3.25%
Debt instrument, term	30 years
Principal Amount	$ 300,000,000			$ 300,000,000
Unamortized (Discount) Premium				(4,000,000)
Unamortized Debt Issuance Costs				(3,000,000)
Long term debt				$ 293,000,000