Segment Information (Segment Select Balance Sheet) (Detail) - USD ($) $ in Millions	Sep. 27, 2019	Dec. 28, 2018
Segment Reporting Information [Line Items]
Accounts receivable, net	$ 488.9	$ 512.6
Inventory, Net	290.1	298.0
Goodwill	3,534.4	3,540.0
Buildings and Infrastructure [Member]
Segment Reporting Information [Line Items]
Accounts receivable, net	175.3	177.5
Inventory, Net	61.3	70.3
Goodwill	1,957.3	1,970.2
Geospatial [Member]
Segment Reporting Information [Line Items]
Accounts receivable, net	109.1	118.7
Inventory, Net	123.0	133.5
Goodwill	397.4	403.1
Resources and Utilities [Member]
Segment Reporting Information [Line Items]
Accounts receivable, net	73.7	83.8
Inventory, Net	44.9	46.2
Goodwill	321.9	305.7
Transportation [Member]
Segment Reporting Information [Line Items]
Accounts receivable, net	130.8	132.6
Inventory, Net	60.9	48.0
Goodwill	$ 857.8	$ 861.0

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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