Segment Information (Schedule Of Revenue, Operating Income And Identifiable Assets By Segment) (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2016	Oct. 02, 2015	Sep. 30, 2016	Oct. 02, 2015	Jan. 01, 2016
Segment Reporting Information [Line Items]
Revenue	$ 584.1	$ 562.3	$ 1,776.7	$ 1,730.7
Consolidated segment operating income	55.3	46.0	125.7	121.5
Depreciation expense			27.9	27.0
Accounts receivable	369.2		369.2		$ 361.9
Inventories	224.3		224.3		261.1
Goodwill	2,111.1		2,111.1		2,106.4
Engineering And Construction [Member]
Segment Reporting Information [Line Items]
Revenue	332.4	326.4	993.4	964.2
Accounts receivable	214.1		214.1		215.9
Inventories	146.7		146.7		178.0
Goodwill	1,149.3		1,149.3		1,140.1
Field Solutions [Member]
Segment Reporting Information [Line Items]
Revenue	77.9	73.5	271.0	275.9
Accounts receivable	59.3		59.3		57.1
Inventories	32.6		32.6		36.0
Goodwill	126.6		126.6		125.7
Mobile Solutions [Member]
Segment Reporting Information [Line Items]
Revenue	138.5	131.6	412.9	388.1
Accounts receivable	71.7		71.7		69.6
Inventories	30.9		30.9		30.4
Goodwill	814.8		814.8		820.7
Advanced Devices [Member]
Segment Reporting Information [Line Items]
Revenue	35.3	30.8	99.4	102.5
Accounts receivable	24.1		24.1		19.3
Inventories	14.1		14.1		16.7
Goodwill	20.4		20.4		$ 19.9
Operating Segments [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	127.9	122.2	352.8	350.9
Depreciation expense	5.1	5.3	15.9	15.9
Operating Segments [Member] \| Engineering And Construction [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	69.1	68.8	175.0	166.3
Depreciation expense	3.2	3.5	10.4	10.6
Operating Segments [Member] \| Field Solutions [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	22.1	19.5	81.5	85.0
Depreciation expense	0.3	0.3	0.9	0.9
Operating Segments [Member] \| Mobile Solutions [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	22.4	23.1	60.2	62.5
Depreciation expense	1.4	1.4	4.1	4.0
Operating Segments [Member] \| Advanced Devices [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	14.3	10.8	36.1	37.1
Depreciation expense	$ 0.2	$ 0.1	$ 0.5	$ 0.4

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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