Valuation And Qualifying Accounts (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Allowance for Doubtful Accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 60	$ 52	$ 39
Expense (Benefit)	107	73	41
Other Adjustments	(2)	3	0
Deductions	(81)	(68)	(28)
Balance at End of Period	84	60	52
Tax Valuation Allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	207	214	311
Expense (Benefit)	(35)	(1)	(95)
Other Adjustments	(3)	(6)	(2)
Deductions	0	0	0
Balance at End of Period	$ 169	$ 207	$ 214