Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Estimated fair values of debt instruments	$ 15,400	$ 16,900
Outstanding principal amount of debt instruments	12,799	13,299
Unamortized discounts and issuance costs	(1,123)	(1,130)
Interest rate swaps | Designated as hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate notional amount of derivatives	500	572
Foreign currency contracts | Designated as hedges
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate notional amount of derivatives	$ 4,000	$ 3,400