Stock-Based Compensation - Schedule of Total Stock-Based Compensation Expense Included in Company's Consolidated Statements of Income and Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	$ 7.4	$ 7.4	$ 22.7	$ 42.1
Cost of Revenues [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	1.2	0.8	3.1	1.9
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	1.0	1.0	3.0	2.8
Selling, General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	5.1	4.0	15.9	16.2
Acquisition and Integration Cost [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense	$ 0.1	1.2	$ 0.7	20.8
Restructuring Related Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Total pre-tax stock-based compensation expense		$ 0.4		$ 0.4