Business Combinations (Changes In Carrying Amount Of Goodwill By Operating Segment) (Detail) $ in Millions	3 Months Ended
Mar. 29, 2019 USD ($)
Goodwill [Line Items]
Balance as of fiscal year 2018	$ 3,540.0
Purchase price adjustments- prior years' acquisitions	(0.7)
Foreign currency translation adjustments	1.5
Balance as of the end of the first quarter of fiscal 2019	3,540.8
Buildings and Infrastructure [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	1,970.2
Purchase price adjustments- prior years' acquisitions	(0.3)
Foreign currency translation adjustments	3.4
Balance as of the end of the first quarter of fiscal 2019	1,973.3
Geospatial [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	403.1
Purchase price adjustments- prior years' acquisitions	0.0
Foreign currency translation adjustments	(1.6)
Balance as of the end of the first quarter of fiscal 2019	401.5
Resources and Utilities [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	305.7
Purchase price adjustments- prior years' acquisitions	0.0
Foreign currency translation adjustments	(0.5)
Balance as of the end of the first quarter of fiscal 2019	305.2
Transportation [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	861.0
Purchase price adjustments- prior years' acquisitions	(0.4)
Foreign currency translation adjustments	0.2
Balance as of the end of the first quarter of fiscal 2019	$ 860.8

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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-Name Accounting Standards Codification
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