Provision for (Benefit from) Income Taxes (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current
Federal		$ (3)	$ (7)	$ 0
State		41	36	5
Foreign		50	59	37
Current income tax provision (benefit)		88	88	42
Deferred
Federal		41	63	(205)
State		(37)	(39)	(5)
Foreign		(107)	(10)	18
Deferred income tax provision		103	(14)	192
Provision for (benefit from) income taxes		$ (15)	102	(150)
Provision adjustment due to corporate tax rate change [Member]
Deferred
Deferred income tax provision			$ (30)	(317)
Provision adjustment due to anticipated repatriation of foreign earnings [Member]
Deferred
Deferred income tax provision	$ (30)			$ (104)