Indebtedness - Fair Value and Carrying Value of Long-Term Debt (Detail) - USD ($) $ in Millions		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]
Carrying Amount		$ 6,303	$ 6,303	$ 5,581
Estimated Fair Value		6,584	6,584	6,078
4.50% 2012 Senior Notes, due 2022
Debt Instrument [Line Items]
Carrying Amount		516	516	507
Estimated Fair Value		$ 521	$ 521	$ 531
Notes payable, interest rate		4.50%	4.50%	4.50%
4.875% 2013 Senior Notes, due 2024
Debt Instrument [Line Items]
Carrying Amount		$ 498	$ 498	$ 497
Estimated Fair Value		$ 536	$ 536	$ 551
Notes payable, interest rate		4.875%	4.875%	4.875%
5.25% 2014 Senior Notes (30-Year), due 2044
Debt Instrument [Line Items]
Carrying Amount		$ 598	$ 598	$ 599
Estimated Fair Value		$ 738	$ 738	$ 757
Notes payable, interest rate		5.25%	5.25%	5.25%
Debt instrument, term			30 years	30 years
1.75% 2015 Senior Notes, due 2027
Debt Instrument [Line Items]
Carrying Amount		$ 546	$ 546	$ 558
Estimated Fair Value		$ 577	$ 577	$ 604
Notes payable, interest rate		1.75%	1.75%	1.75%
2.75% 2017 Senior Notes, due 2021
Debt Instrument [Line Items]
Carrying Amount		$ 520	$ 520	$ 508
Estimated Fair Value		$ 497	$ 497	$ 507
Notes payable, interest rate		2.75%	2.75%	2.75%
2.625% 2017 Senior Notes, due 2023
Debt Instrument [Line Items]
Carrying Amount		$ 512	$ 512	$ 504
Estimated Fair Value		$ 496	$ 496	$ 507
Notes payable, interest rate		2.625%	2.625%	2.625%
3.25% 2017 Senior Notes, due 2028
Debt Instrument [Line Items]
Carrying Amount		$ 524	$ 524	$ 493
Estimated Fair Value		$ 509	$ 509	$ 523
Notes payable, interest rate		3.25%	3.25%	3.25%
3.25% 2018 Senior Notes, due 2021
Debt Instrument [Line Items]
Carrying Amount		$ 299	$ 299	$ 299
Estimated Fair Value		$ 301	$ 301	$ 306
Notes payable, interest rate		3.25%	3.25%	3.25%
4.25% 2018 Senior Notes, due 2029
Debt Instrument [Line Items]
Carrying Amount		$ 394	$ 394	$ 394
Estimated Fair Value		$ 445	$ 445	$ 453
Notes payable, interest rate		4.25%	4.25%	4.25%
4.875% 2018 Senior Notes, due 2048
Debt Instrument [Line Items]
Carrying Amount		$ 389	$ 389	$ 389
Estimated Fair Value		$ 463	$ 463	$ 492
Notes payable, interest rate		4.875%	4.875%	4.875%
0.950% Senior Notes Due 2030
Debt Instrument [Line Items]
Carrying Amount		$ 814	$ 814	$ 833
Estimated Fair Value		$ 769	$ 769	$ 847
Notes payable, interest rate		0.95%	0.95%	0.95%
3.75% 2020 Senior Note, due 2025
Debt Instrument [Line Items]
Carrying Amount		$ 693	$ 693
Estimated Fair Value		$ 732	$ 732
Notes payable, interest rate	3.75%	3.75%	3.75%
Debt instrument, term	5 years	5 years

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

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

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
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