SCHEDULE II-VALUATION AND QUALIFYING ACCOUNTS (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Allowance for loss on receivables:
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ (96)	$ (118)	$ (101)
Acquired/(Disposed) Balances	0	0	0
Charged (Credited) to Costs and Expenses	36	20	39
Charged to Other Accounts	(29)	(10)	19
Deductions or Write-offs	(24)	(32)	(41)
Balance at End of Period	(79)	(96)	(118)
Deferred tax asset valuation allowance:
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	(49)	(49)	(42)
Acquired/(Disposed) Balances	0	0	0
Charged (Credited) to Costs and Expenses	(5)	0	(7)
Charged to Other Accounts	0	0	0
Deductions or Write-offs	0	0	0
Balance at End of Period	$ (54)	$ (49)	$ (49)