Financial Income, Net (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortization of marketable securities premium and accretion of discount, net	$ 9.4	$ 2.0	$ 13.6
Realized loss (gain) on sale of marketable securities, net	(4.5)	(0.7)	1.8
Financial income, net	66.6	80.6	65.1
Financial Income
Schedule of Trading Securities and Other Trading Assets [Line Items]
Interest income	78.2	93.3	88.5
Financial Expense
Schedule of Trading Securities and Other Trading Assets [Line Items]
Amortization of marketable securities premium and accretion of discount, net	9.4	2.0	13.6
Realized loss (gain) on sale of marketable securities, net	(4.5)	(0.7)	1.8
Foreign currency re-measurement loss	4.5	8.9	5.7
Others	2.2	2.5	2.3
Total financial expense	$ 11.6	$ 12.7	$ 23.4

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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