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Cost-Reduction Actions - Additional Information (Detail) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($) employee	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($) employee	Jun. 30, 2019 USD ($)
Restructuring Cost and Reserve [Line Items]
Cost-reduction charges and other costs	$ 7.9	$ 2.6	$ 35.4	$ 5.2
Charges (credits) related to work-force reductions	(3.0)		5.5
Cost of revenue \| Services
Restructuring Cost and Reserve [Line Items]
Cost-reduction charges and other costs	6.9	(1.0)	12.8	(4.7)
Selling, general and administrative expenses
Restructuring Cost and Reserve [Line Items]
Cost-reduction charges and other costs	1.5	3.6	4.0	8.6
Research and development expenses
Restructuring Cost and Reserve [Line Items]
Cost-reduction charges and other costs	0.1		0.2	1.3
Other expense, net
Restructuring Cost and Reserve [Line Items]
Cost-reduction charges and other costs	(0.6)		18.4
Employee severance
Restructuring Cost and Reserve [Line Items]
Cost-reduction charges and other costs			11.3
Charges (credits) related to work-force reductions	$ 1.6		$ 11.3
Number of employees \| employee	19		309
Changes in estimates
Restructuring Cost and Reserve [Line Items]
Charges (credits) related to work-force reductions	$ (4.6)	1.8	$ (5.8)	0.9
Net foreign currency (gains) losses
Restructuring Cost and Reserve [Line Items]
Other charges (credits) related to the cost-reduction effort	(0.6)		18.4
Asset impairments
Restructuring Cost and Reserve [Line Items]
Other charges (credits) related to the cost-reduction effort	$ 11.5		$ 11.5
Lease abandonment costs and asset write-offs
Restructuring Cost and Reserve [Line Items]
Other charges (credits) related to the cost-reduction effort		$ 0.8		$ 4.3