Business Segment, Geographic Area, Product/Service Offerings and Significant Customer Information - Reconciliation of Segment Gross Profit to Consolidated Net Income (Detail) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Gross profit	$ 301.6	$ 262.0	$ 246.3	$ 239.6	$ 216.3	$ 205.0	$ 211.0	$ 198.1	$ 1,049.5	$ 830.4	$ 979.5
Research and development									173.1	164.1	135.7
Selling, general and administrative									353.1	330.3	298.1
Acquisition and integration costs									3.8	37.3	3.1
Restructuring and other									9.4	7.0	4.6
Amortization of intangible assets									55.2	67.4	43.5
Asset impairment									2.3	4.7
COVID-19 related net credits									(1.2)
Fees and expenses related to repricing of Term Loan Facility										6.6	0.4
Gain on sale of long-lived assets										(6.8)
Income from operations	146.7	116.4	100.8	89.9	66.1	66.8	63.9	23.1	453.8	219.8	494.1
Interest income									1.4	5.4	5.8
Interest expense									29.1	44.1	16.9
Other expense, net									3.1	3.3	2.0
Income before income taxes									423.0	177.8	481.0
Provision for income taxes									72.9	37.4	88.1
Net income	$ 115.6	$ 91.7	$ 73.7	$ 69.1	$ 42.8	$ 47.4	$ 37.7	$ 12.5	350.1	140.4	392.9
Vacuum & Analysis [Member]
Segment Reporting Information [Line Items]
Gross profit									633.7	426.4	577.6
Light & Motion [Member]
Segment Reporting Information [Line Items]
Gross profit									309.8	336.8	$ 401.9
Equipment & Solutions [Member]
Segment Reporting Information [Line Items]
Gross profit									$ 106.0	$ 67.2