Indebtedness - Principal Payments Due on Long-Term Borrowings (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
2022	$ 0
2023	500
2024	500
2025	700
2026	0
Thereafter	5,821
Total principal payment	7,521	$ 6,430
4.50% 2012 Senior Notes, due 2022
Debt Instrument [Line Items]
Total principal payment		500
4.875% 2013 Senior Notes, due 2024
Debt Instrument [Line Items]
2024	500
Total principal payment	500	500
5.25% 2014 Senior Notes, due 2044
Debt Instrument [Line Items]
Thereafter	600
Total principal payment	600	600
1.75% 2015 Senior Notes, due 2027
Debt Instrument [Line Items]
Thereafter	568
Total principal payment	568	612
2.625% 2017 Senior Notes, due 2023
Debt Instrument [Line Items]
2023	500
Total principal payment	500	500
2017 Senior Notes due 2028
Debt Instrument [Line Items]
Thereafter	500
Total principal payment	500
4.25% 2018 Senior Notes, due 2029
Debt Instrument [Line Items]
Thereafter	400
Total principal payment	400	400
4.875% 2018 Senior Notes, due 2048
Debt Instrument [Line Items]
Thereafter	400
Total principal payment	400	400
0.950% 2019 Senior Note, due 2030
Debt Instrument [Line Items]
Thereafter	853
Total principal payment	853
3.75% 2020 Senior Notes, due 2025
Debt Instrument [Line Items]
2025	700
Total principal payment	700	700
3.25% 2020 Senior Notes, due 2050
Debt Instrument [Line Items]
Thereafter	300
Total principal payment	300	300
2.55% 2020 Senior Notes, due 2060
Debt Instrument [Line Items]
Thereafter	500
Total principal payment	500	$ 500
2.00% 2021 Senior Notes, due 2031
Debt Instrument [Line Items]
Thereafter	600
Total principal payment	600
2.75% 2021 Senior Notes, due 2041
Debt Instrument [Line Items]
Thereafter	600
Total principal payment	600
3.10% 2021 Senior Notes, due 2061
Debt Instrument [Line Items]
Thereafter	500
Total principal payment	$ 500

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

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