Intangible Assets and Goodwill (Changes In Carrying Amount Of Goodwill By Operating Segment) (Detail) $ in Millions	9 Months Ended
Oct. 01, 2021 USD ($)
Goodwill [Roll Forward]
Balance as of year end 2020	$ 3,876.5
Decrease from the sale of businesses	(18.0)
Foreign currency translation and other adjustments	(34.9)
Balance as of the end of the third quarter of 2021	3,823.6
Buildings and Infrastructure
Goodwill [Roll Forward]
Balance as of year end 2020	1,997.4
Decrease from the sale of businesses	(14.7)
Foreign currency translation and other adjustments	(8.2)
Balance as of the end of the third quarter of 2021	1,974.5
Geospatial
Goodwill [Roll Forward]
Balance as of year end 2020	415.7
Decrease from the sale of businesses	0.0
Foreign currency translation and other adjustments	(7.9)
Balance as of the end of the third quarter of 2021	407.8
Resources and Utilities
Goodwill [Roll Forward]
Balance as of year end 2020	453.8
Decrease from the sale of businesses	(3.3)
Foreign currency translation and other adjustments	(6.6)
Balance as of the end of the third quarter of 2021	443.9
Transportation
Goodwill [Roll Forward]
Balance as of year end 2020	1,009.6
Decrease from the sale of businesses	0.0
Foreign currency translation and other adjustments	(12.2)
Balance as of the end of the third quarter of 2021	$ 997.4

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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