Business Combinations (Changes In Carrying Amount Of Goodwill By Operating Segment) (Detail) $ in Millions	9 Months Ended
Sep. 27, 2019 USD ($)
Goodwill [Line Items]
Balance as of fiscal year 2018	$ 3,540.0
Additions due to acquisitions	20.2
Purchase price and foreign currency translation adjustments	(25.8)
Balance as of the end of the third quarter of fiscal 2019	3,534.4
Buildings and Infrastructure [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	1,970.2
Additions due to acquisitions	0.3
Purchase price and foreign currency translation adjustments	(13.2)
Balance as of the end of the third quarter of fiscal 2019	1,957.3
Geospatial [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	403.1
Purchase price and foreign currency translation adjustments	(5.7)
Balance as of the end of the third quarter of fiscal 2019	397.4
Resources and Utilities [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	305.7
Additions due to acquisitions	19.9
Purchase price and foreign currency translation adjustments	(3.7)
Balance as of the end of the third quarter of fiscal 2019	321.9
Transportation [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	861.0
Purchase price and foreign currency translation adjustments	(3.2)
Balance as of the end of the third quarter of fiscal 2019	$ 857.8

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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