Segment Information (Schedule Of Revenue, Operating Income And Identifiable Assets By Segment) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 01, 2022	Jul. 02, 2021	Jul. 01, 2022	Jul. 02, 2021
Segment Reporting Information [Line Items]
Segment operating income	$ 134.9	$ 144.8	$ 291.8	$ 285.7
Depreciation expense			20.0	20.8
Operating segment
Segment Reporting Information [Line Items]
Segment revenue	941.2	945.3	1,934.9	1,832.0
Segment operating income	244.0	253.5	506.9	487.1
Depreciation expense	5.4	6.2	11.1	12.1
Buildings and Infrastructure | Operating segment
Segment Reporting Information [Line Items]
Segment revenue	382.6	364.8	780.2	707.9
Segment operating income	101.4	104.1	222.1	200.5
Depreciation expense	1.6	1.8	3.2	3.6
Geospatial | Operating segment
Segment Reporting Information [Line Items]
Segment revenue	193.7	219.7	401.2	401.4
Segment operating income	57.8	66.1	115.7	114.8
Depreciation expense	1.5	1.8	3.1	3.5
Resources and Utilities | Operating segment
Segment Reporting Information [Line Items]
Segment revenue	214.8	197.5	444.7	402.7
Segment operating income	73.0	70.5	148.1	150.6
Depreciation expense	1.4	1.5	2.9	3.0
Transportation | Operating segment
Segment Reporting Information [Line Items]
Segment revenue	150.1	163.3	308.8	320.0
Segment operating income	11.8	12.8	21.0	21.2
Depreciation expense	$ 0.9	$ 1.1	$ 1.9	$ 2.0