Indebtedness - Summary of Total Indebtedness (Detail) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Principal Amount	$ 7,991	$ 7,521
Fair Value of Interest Rate Swap	(95)	(10)
Unamortized (Discount) Premium	(57)	(48)
Unamortized Debt Issuance Costs	(53)	(50)
Carrying Amount	7,786	7,413
Current portion	(501)	0
Long term debt	$ 7,285	$ 7,413
4.875% 2013 Senior Notes, due 2024
Debt Instrument [Line Items]
Notes payable, interest rate	4.875%	4.875%
Principal Amount	$ 500	$ 500
Fair Value of Interest Rate Swap	0	0
Unamortized (Discount) Premium	(1)	(1)
Unamortized Debt Issuance Costs	(1)	(1)
Carrying Amount	$ 498	$ 498
5.25% 2014 Senior Notes, due 2044
Debt Instrument [Line Items]
Notes payable, interest rate	5.25%	5.25%
Principal Amount	$ 600	$ 600
Fair Value of Interest Rate Swap	(24)	(7)
Unamortized (Discount) Premium	3	3
Unamortized Debt Issuance Costs	(5)	(5)
Carrying Amount	$ 574	$ 591
1.75% 2015 Senior Notes, due 2027
Debt Instrument [Line Items]
Notes payable, interest rate	1.75%	1.75%
Principal Amount	$ 556	$ 568
Fair Value of Interest Rate Swap	0	0
Unamortized (Discount) Premium	0	0
Unamortized Debt Issuance Costs	(2)	(2)
Carrying Amount	$ 554	$ 566
2.625% 2017 Senior Notes, due 2023
Debt Instrument [Line Items]
Notes payable, interest rate	2.625%	2.625%
Principal Amount	$ 500	$ 500
Fair Value of Interest Rate Swap	2	5
Unamortized (Discount) Premium	0	0
Unamortized Debt Issuance Costs	(1)	(1)
Carrying Amount	$ 501	$ 504
3.25% 2017 Senior Notes, due 2028
Debt Instrument [Line Items]
Notes payable, interest rate	3.25%	3.25%
Principal Amount	$ 500	$ 500
Fair Value of Interest Rate Swap	(16)	8
Unamortized (Discount) Premium	(3)	(3)
Unamortized Debt Issuance Costs	(2)	(2)
Carrying Amount	$ 479	$ 503
4.25% 2018 Senior Notes, due 2029
Debt Instrument [Line Items]
Notes payable, interest rate	4.25%	4.25%
Principal Amount	$ 400	$ 400
Fair Value of Interest Rate Swap	(12)	0
Unamortized (Discount) Premium	(2)	(2)
Unamortized Debt Issuance Costs	(2)	(2)
Carrying Amount	$ 384	$ 396
4.875% 2018 Senior Notes, due 2048
Debt Instrument [Line Items]
Notes payable, interest rate	4.875%	4.875%
Principal Amount	$ 400	$ 400
Fair Value of Interest Rate Swap	(25)	(7)
Unamortized (Discount) Premium	(6)	(6)
Unamortized Debt Issuance Costs	(4)	(4)
Carrying Amount	$ 365	$ 383
0.950% Senior Notes Due 2030
Debt Instrument [Line Items]
Notes payable, interest rate	0.95%	0.95%
Principal Amount	$ 835	$ 853
Fair Value of Interest Rate Swap	0	0
Unamortized (Discount) Premium	(2)	(2)
Unamortized Debt Issuance Costs	(5)	(5)
Carrying Amount	$ 828	$ 846
3.75% 2020 Senior Notes, due 2025
Debt Instrument [Line Items]
Notes payable, interest rate	3.75%	3.75%
Principal Amount	$ 700	$ 700
Fair Value of Interest Rate Swap	(20)	(9)
Unamortized (Discount) Premium	(1)	(1)
Unamortized Debt Issuance Costs	(3)	(4)
Carrying Amount	$ 676	$ 686
3.25% 2020 Senior Notes, due 2050
Debt Instrument [Line Items]
Notes payable, interest rate	3.25%	3.25%
Principal Amount	$ 300	$ 300
Fair Value of Interest Rate Swap	0	0
Unamortized (Discount) Premium	(4)	(4)
Unamortized Debt Issuance Costs	(3)	(3)
Carrying Amount	$ 293	$ 293
2.55% 2020 Senior Notes, due 2060
Debt Instrument [Line Items]
Notes payable, interest rate	2.55%	2.55%
Principal Amount	$ 500	$ 500
Fair Value of Interest Rate Swap	0	0
Unamortized (Discount) Premium	(4)	(4)
Unamortized Debt Issuance Costs	(5)	(5)
Carrying Amount	$ 491	$ 491
2.00% 2021 Senior Notes, due 2031
Debt Instrument [Line Items]
Notes payable, interest rate	2.00%	2.00%
Principal Amount	$ 600	$ 600
Fair Value of Interest Rate Swap	0	0
Unamortized (Discount) Premium	(8)	(8)
Unamortized Debt Issuance Costs	(5)	(5)
Carrying Amount	$ 587	$ 587
2.75% 2021 Senior Notes, due 2041
Debt Instrument [Line Items]
Notes payable, interest rate	2.75%	2.75%
Principal Amount	$ 600	$ 600
Fair Value of Interest Rate Swap	0	0
Unamortized (Discount) Premium	(13)	(13)
Unamortized Debt Issuance Costs	(5)	(6)
Carrying Amount	$ 582	$ 581
3.10% 2021 Senior Notes, due 2061
Debt Instrument [Line Items]
Notes payable, interest rate	3.10%	3.10%
Principal Amount	$ 500	$ 500
Fair Value of Interest Rate Swap	0	0
Unamortized (Discount) Premium	(7)	(7)
Unamortized Debt Issuance Costs	(5)	(5)
Carrying Amount	$ 488	$ 488
3.75% 2022 Senior Notes, due 2052
Debt Instrument [Line Items]
Notes payable, interest rate	3.75%
Principal Amount	$ 500
Fair Value of Interest Rate Swap	0
Unamortized (Discount) Premium	(9)
Unamortized Debt Issuance Costs	(5)
Carrying Amount	$ 486

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

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