v3.20.4

Income Taxes - Reconciliation of Unrecognized Tax Benefits (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Balance as of January 1,	$ 159	$ 165	$ 177
Translation differences	0	(1)	(4)
Lapse of statute of limitations	(4)	(3)	0
Increases from tax positions taken during prior periods	5	4	7
Decreases from tax positions taken during prior periods	0	(4)	(17)
Increases from tax positions taken during current period	7	7	7
Decreases relating to settlements with the tax authorities	(6)	(9)	(5)
Balance as of December 31,	$ 161	$ 159	$ 165

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