Indebtedness - Summary of Total Indebtedness (Detail) - USD ($)		1 Months Ended	3 Months Ended	12 Months Ended
Mar. 25, 2020	Mar. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal Amount		$ 6,759,000,000	$ 6,759,000,000	$ 5,603,000,000
Fair Value of Interest Rate Swap		85,000,000	85,000,000	27,000,000
Unamortized (Discount) Premium		(20,000,000)	(20,000,000)	(17,000,000)
Unamortized Debt Issuance Costs		(36,000,000)	(36,000,000)	(32,000,000)
Long term debt		6,303,000,000	6,303,000,000	$ 5,581,000,000
Short-term debt		485,000,000	485,000,000
Total debt		6,788,000,000	6,788,000,000
Commercial Paper
Debt Instrument [Line Items]
Principal Amount		487,000,000	487,000,000
Unamortized (Discount) Premium		(2,000,000)	(2,000,000)
Short-term debt		$ 485,000,000	$ 485,000,000
4.50% 2012 Senior Notes, due 2022
Debt Instrument [Line Items]
Notes payable, interest rate		4.50%	4.50%	4.50%
Principal Amount		$ 500,000,000	$ 500,000,000	$ 500,000,000
Fair Value of Interest Rate Swap		18,000,000	18,000,000	9,000,000
Unamortized (Discount) Premium		(1,000,000)	(1,000,000)	(1,000,000)
Unamortized Debt Issuance Costs		(1,000,000)	(1,000,000)	(1,000,000)
Long term debt		$ 516,000,000	$ 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%	4.875%
Principal Amount		$ 500,000,000	$ 500,000,000	$ 500,000,000
Unamortized (Discount) Premium		(1,000,000)	(1,000,000)	(1,000,000)
Unamortized Debt Issuance Costs		(1,000,000)	(1,000,000)	(2,000,000)
Long term debt		$ 498,000,000	$ 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%	5.25%
Debt instrument, term			30 years	30 years
Principal Amount		$ 600,000,000	$ 600,000,000	$ 600,000,000
Unamortized (Discount) Premium		3,000,000	3,000,000	4,000,000
Unamortized Debt Issuance Costs		(5,000,000)	(5,000,000)	(5,000,000)
Long term debt		$ 598,000,000	$ 598,000,000	$ 599,000,000
1.75% 2015 Senior Notes, due 2027
Debt Instrument [Line Items]
Notes payable, interest rate		1.75%	1.75%	1.75%
Principal Amount		$ 549,000,000	$ 549,000,000	$ 561,000,000
Unamortized (Discount) Premium		0	0	0
Unamortized Debt Issuance Costs		(3,000,000)	(3,000,000)	(3,000,000)
Long term debt		$ 546,000,000	$ 546,000,000	$ 558,000,000
2.75% 2017 Senior Notes, due 2021
Debt Instrument [Line Items]
Notes payable, interest rate		2.75%	2.75%	2.75%
Principal Amount		$ 500,000,000	$ 500,000,000	$ 500,000,000
Fair Value of Interest Rate Swap		21,000,000	21,000,000	11,000,000
Unamortized (Discount) Premium		0	0	(1,000,000)
Unamortized Debt Issuance Costs		(1,000,000)	(1,000,000)	(2,000,000)
Long term debt		$ 520,000,000	$ 520,000,000	$ 508,000,000
2.625% 2017 Senior Notes, due 2023
Debt Instrument [Line Items]
Notes payable, interest rate		2.625%	2.625%	2.625%
Principal Amount		$ 500,000,000	$ 500,000,000	$ 500,000,000
Fair Value of Interest Rate Swap		15,000,000	15,000,000	7,000,000
Unamortized (Discount) Premium		(1,000,000)	(1,000,000)	(1,000,000)
Unamortized Debt Issuance Costs		(2,000,000)	(2,000,000)	(2,000,000)
Long term debt		$ 512,000,000	$ 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%	3.25%
Principal Amount		$ 500,000,000	$ 500,000,000	$ 500,000,000
Fair Value of Interest Rate Swap		31,000,000	31,000,000
Unamortized (Discount) Premium		(4,000,000)	(4,000,000)	(4,000,000)
Unamortized Debt Issuance Costs		(3,000,000)	(3,000,000)	(3,000,000)
Long term debt		$ 524,000,000	$ 524,000,000	$ 493,000,000
3.25% 2018 Senior Notes, due 2021
Debt Instrument [Line Items]
Notes payable, interest rate		3.25%	3.25%	3.25%
Principal Amount		$ 300,000,000	$ 300,000,000	$ 300,000,000
Fair Value of Interest Rate Swap		0	0
Unamortized (Discount) Premium		0	0	0
Unamortized Debt Issuance Costs		(1,000,000)	(1,000,000)	(1,000,000)
Long term debt		$ 299,000,000	$ 299,000,000	$ 299,000,000
4.25% 2018 Senior Notes, due 2029
Debt Instrument [Line Items]
Notes payable, interest rate		4.25%	4.25%	4.25%
Principal Amount		$ 400,000,000	$ 400,000,000	$ 400,000,000
Unamortized (Discount) Premium		(3,000,000)	(3,000,000)	(3,000,000)
Unamortized Debt Issuance Costs		(3,000,000)	(3,000,000)	(3,000,000)
Long term debt		$ 394,000,000	$ 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%	4.875%
Principal Amount		$ 400,000,000	$ 400,000,000	$ 400,000,000
Unamortized (Discount) Premium		(7,000,000)	(7,000,000)	(7,000,000)
Unamortized Debt Issuance Costs		(4,000,000)	(4,000,000)	(4,000,000)
Long term debt		$ 389,000,000	$ 389,000,000	$ 389,000,000
0.950% Senior Notes Due 2030
Debt Instrument [Line Items]
Notes payable, interest rate		0.95%	0.95%	0.95%
Principal Amount		$ 823,000,000	$ 823,000,000	$ 842,000,000
Unamortized (Discount) Premium		(3,000,000)	(3,000,000)	(3,000,000)
Unamortized Debt Issuance Costs		(6,000,000)	(6,000,000)	(6,000,000)
Long term debt		$ 814,000,000	$ 814,000,000	$ 833,000,000
3.75% 2020 Senior Note, due 2025
Debt Instrument [Line Items]
Notes payable, interest rate	3.75%	3.75%	3.75%
Debt instrument, term	5 years	5 years
Principal Amount	$ 700,000,000	$ 700,000,000	$ 700,000,000
Unamortized (Discount) Premium		(1,000,000)	(1,000,000)
Unamortized Debt Issuance Costs		(6,000,000)	(6,000,000)
Long term debt		$ 693,000,000	$ 693,000,000

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

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