Segment Information (Schedule Of Revenue, Operating Income And Identifiable Assets By Segment) (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Oct. 02, 2015	Oct. 03, 2014	Oct. 02, 2015	Oct. 03, 2014	Jan. 02, 2015
Segment Reporting Information [Line Items]
Segment revenue	$ 562.3	$ 584.8	$ 1,730.7	$ 1,831.7
Consolidated segment operating income	46.0	11.1	121.5	184.0
Depreciation expense			27.0	24.1
Accounts receivable	344.5		344.5		$ 362.0
Inventories	271.4		271.4		278.1
Goodwill	2,083.7		2,083.7		2,085.8
Engineering And Construction [Member]
Segment Reporting Information [Line Items]
Segment revenue	326.4	342.2	964.2	1,019.6
Accounts receivable	210.5		210.5		227.7
Inventories	187.4		187.4		185.2
Goodwill	1,147.9		1,147.9		1,170.6
Field Solutions [Member]
Segment Reporting Information [Line Items]
Segment revenue	73.5	88.8	275.9	341.4
Accounts receivable	45.2		45.2		51.6
Inventories	39.9		39.9		51.0
Goodwill	106.4		106.4		96.0
Mobile Solutions [Member]
Segment Reporting Information [Line Items]
Segment revenue	131.6	121.2	388.1	362.7
Accounts receivable	66.8		66.8		62.9
Inventories	28.6		28.6		26.1
Goodwill	808.0		808.0		796.0
Advanced Devices [Member]
Segment Reporting Information [Line Items]
Segment revenue	30.8	32.6	102.5	108.0
Accounts receivable	22.0		22.0		19.8
Inventories	15.5		15.5		15.8
Goodwill	21.4		21.4		$ 23.2
Operating Segments [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	122.2	129.4	350.9	443.3
Depreciation expense	5.3	5.3	15.9	14.8
Operating Segments [Member] \| Engineering And Construction [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	68.8	74.2	166.3	231.0
Depreciation expense	3.5	3.4	10.6	9.7
Operating Segments [Member] \| Field Solutions [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	19.5	26.1	85.0	119.4
Depreciation expense	0.3	0.2	0.9	0.6
Operating Segments [Member] \| Mobile Solutions [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	23.1	19.5	62.5	58.5
Depreciation expense	1.4	1.5	4.0	4.0
Operating Segments [Member] \| Advanced Devices [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	10.8	9.6	37.1	34.4
Depreciation expense	$ 0.1	$ 0.2	$ 0.4	$ 0.5

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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