Business Combinations (Schedule Of Changes In Carrying Amount Of Goodwill) (Details) $ in Millions	12 Months Ended
Jan. 01, 2021 USD ($)
Goodwill [Roll Forward]
Beginning Balance	$ 3,680.6
Additions due to acquisitions	149.3
Purchase price and foreign currency translation adjustments	46.6
Ending Balance	3,876.5
Buildings and Infrastructure
Goodwill [Roll Forward]
Beginning Balance	1,973.0
Additions due to acquisitions	1.3
Purchase price and foreign currency translation adjustments	23.1
Ending Balance	1,997.4
Geospatial
Goodwill [Roll Forward]
Beginning Balance	401.5
Additions due to acquisitions	0.0
Purchase price and foreign currency translation adjustments	14.2
Ending Balance	415.7
Resources and Utilities
Goodwill [Roll Forward]
Beginning Balance	445.4
Additions due to acquisitions	0.4
Purchase price and foreign currency translation adjustments	8.0
Ending Balance	453.8
Transportation
Goodwill [Roll Forward]
Beginning Balance	860.7
Additions due to acquisitions	147.6
Purchase price and foreign currency translation adjustments	1.3
Ending Balance	$ 1,009.6

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(10)(1))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120320667&loc=SL49117168-202975

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e961-128460

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-URI http://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

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