Quarterly Financial Data (Unaudited) - Quarterly Financial Data by Segment (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 29, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 30, 2018	Sep. 30, 2018	Jul. 01, 2018	Apr. 01, 2018	Dec. 29, 2019	Dec. 30, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Net Sales	$ 834.2	$ 802.2	$ 782.0	$ 745.2	$ 748.4	$ 725.3	$ 732.5	$ 695.6	$ 3,163.6	$ 2,901.8	$ 2,603.8
Operating Income	133.8	128.7	131.9	97.3	111.2	105.5	111.5	88.4	491.7	416.6	321.7
Instrumentation
Segment Reporting Information [Line Items]
Net Sales									1,105.1	1,021.2	953.9
Digital Imaging
Segment Reporting Information [Line Items]
Net Sales									992.9	875.3
Aerospace and Defense Electronics
Segment Reporting Information [Line Items]
Net Sales									690.1	640.2
Engineered Systems
Segment Reporting Information [Line Items]
Net Sales									375.5	365.1
Operating Segments
Segment Reporting Information [Line Items]
Net Sales									3,163.6	2,901.8	2,603.8
Operating Income									491.7	416.6	321.7
Operating Segments | Instrumentation
Segment Reporting Information [Line Items]
Net Sales	301.6	282.9	264.1	256.5	263.4	256.2	262.6	239.0	1,105.1	1,021.2	953.9
Operating Income	59.5	52.0	49.0	39.9	43.0	35.7	40.9	27.8	200.4	147.4	126.0
Operating Segments | Digital Imaging
Segment Reporting Information [Line Items]
Net Sales	268.1	244.0	248.4	232.4	223.3	220.7	223.0	208.3	992.9	875.3	710.4
Operating Income	47.1	41.2	51.6	36.6	36.3	42.3	43.1	33.8	176.5	155.5	110.2
Operating Segments | Aerospace and Defense Electronics
Segment Reporting Information [Line Items]
Net Sales	170.4	177.1	176.0	166.6	166.0	160.3	157.5	156.4	690.1	640.2	591.2
Operating Income	32.8	39.5	38.6	32.5	35.4	33.0	32.6	30.8	143.4	131.8	113.0
Operating Segments | Engineered Systems
Segment Reporting Information [Line Items]
Net Sales	94.1	98.2	93.5	89.7	95.7	88.1	89.4	91.9	375.5	365.1	348.3
Operating Income	10.5	10.6	9.0	6.4	10.7	9.6	8.7	8.9	36.5	37.9	35.5
Corporate expense
Segment Reporting Information [Line Items]
Operating Income	$ (16.1)	$ (14.6)	$ (16.3)	$ (18.1)	$ (14.2)	$ (15.1)	$ (13.8)	$ (12.9)	$ (65.1)	$ (56.0)	$ (63.0)