Business Combinations (Changes In Carrying Amount Of Goodwill By Operating Segment) (Detail) $ in Millions	6 Months Ended
Jun. 28, 2019 USD ($)
Goodwill [Line Items]
Balance as of fiscal year 2018	$ 3,540.0
Goodwill, Acquired During Period	0.3
Goodwill, Translation and Purchase Accounting Adjustments	1.6
Balance as of the end of the second quarter of fiscal 2019	3,541.9
Buildings and Infrastructure [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	1,970.2
Goodwill, Acquired During Period	0.3
Goodwill, Translation and Purchase Accounting Adjustments	1.6
Balance as of the end of the second quarter of fiscal 2019	1,972.1
Geospatial [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	403.1
Goodwill, Translation and Purchase Accounting Adjustments	(0.5)
Balance as of the end of the second quarter of fiscal 2019	402.6
Resources and Utilities [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	305.7
Goodwill, Translation and Purchase Accounting Adjustments	0.4
Balance as of the end of the second quarter of fiscal 2019	306.1
Transportation [Member]
Goodwill [Line Items]
Balance as of fiscal year 2018	861.0
Goodwill, Translation and Purchase Accounting Adjustments	0.1
Balance as of the end of the second quarter of fiscal 2019	$ 861.1

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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