Segment Information (Segment Select Balance Sheet) (Detail) - USD ($) $ in Millions	Mar. 29, 2019	Dec. 28, 2018
Segment Reporting Information [Line Items]
Accounts receivable, net	$ 525.2	$ 512.6
Inventory, Net	303.7	298.0
Goodwill	3,540.8	3,540.0
Buildings and Infrastructure [Member]
Segment Reporting Information [Line Items]
Accounts receivable, net	186.2	177.5
Inventory, Net	64.7	70.3
Goodwill	1,973.3	1,970.2
Geospatial [Member]
Segment Reporting Information [Line Items]
Accounts receivable, net	111.3	118.7
Inventory, Net	136.7	133.5
Goodwill	401.5	403.1
Resources and Utilities [Member]
Segment Reporting Information [Line Items]
Accounts receivable, net	101.7	83.8
Inventory, Net	43.9	46.2
Goodwill	305.2	305.7
Transportation [Member]
Segment Reporting Information [Line Items]
Accounts receivable, net	126.0	132.6
Inventory, Net	58.4	48.0
Goodwill	$ 860.8	$ 861.0

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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