Business Combinations (Changes In Carrying Amount Of Goodwill By Operating Segment) (Detail) $ in Millions	3 Months Ended
Apr. 03, 2020 USD ($)
Goodwill [Line Items]
Balance as of fiscal year end 2019	$ 3,680.6
Additions due to acquisitions	147.6
Purchase price and foreign currency translation adjustments	(44.6)
Balance as of the end of the first quarter of fiscal 2020	3,783.6
Buildings and Infrastructure [Member]
Goodwill [Line Items]
Balance as of fiscal year end 2019	1,973.0
Additions due to acquisitions	0.0
Purchase price and foreign currency translation adjustments	(18.1)
Balance as of the end of the first quarter of fiscal 2020	1,954.9
Geospatial [Member]
Goodwill [Line Items]
Balance as of fiscal year end 2019	401.5
Purchase price and foreign currency translation adjustments	(7.7)
Balance as of the end of the first quarter of fiscal 2020	393.8
Resources and Utilities [Member]
Goodwill [Line Items]
Balance as of fiscal year end 2019	445.4
Additions due to acquisitions	0.0
Purchase price and foreign currency translation adjustments	(10.8)
Balance as of the end of the first quarter of fiscal 2020	434.6
Transportation [Member]
Goodwill [Line Items]
Balance as of fiscal year end 2019	860.7
Additions due to acquisitions	147.6
Purchase price and foreign currency translation adjustments	(8.0)
Balance as of the end of the first quarter of fiscal 2020	$ 1,000.3

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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