Summary Of Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 5	$ 6	$ 5
Interest cost	21	19	19
Expected return on plan assets	(30)	(33)	(30)
Defined Benefit Plan Amortization Of Unrecognized Amounts	7	7	8
Net periodic benefit cost	3	(1)	2
Employee Benefit Plans [Abstract]
Defined Benefit Plan, Benefit Obligation	821	722	779
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	(87)	32
Defined Benefit Plan, Benefit Obligation, Foreign Currency Translation Gain (Loss)	13	(24)
Defined Benefit Plan, Plan Assets, Amount	649	549	$ 614
Actual return on plan assets	91	(29)
Employer contributions	21	11
Defined Benefit Plan, Plan Assets, Foreign Currency Translation Gain (Loss)	14	(21)
Operating Expense [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	4
Selling, General and Administrative Expenses [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 1	$ 2