Stockholders' Equity (Components Of Other Comprehensive Income) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Equity [Abstract]
Net loss	$ (170)	$ (158)
Other comprehensive income (loss):
Currency translation adjustments (net of tax of $(12) and $(4), respectively)	(14)	(83)
Net unrealized gain (loss) on cash flow hedges (net of tax of $3 and $6, respectively)	35	(18)
Minimum pension liability adjustment (net of tax of $0 and $0, respectively)	3	2
Other comprehensive income (loss)	24	(99)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	(146)	(257)
Currency translation adjustments, tax	(12)	(4)
Net unrealized gain (loss) on cash flow hedges, tax	3	6
Minimum pension liability adjustment, tax	$ 0	$ 0