Segment Information (Schedule Of Revenue, Operating Income And Identifiable Assets By Segment) (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jul. 03, 2015	Jul. 04, 2014	Jul. 03, 2015	Jul. 04, 2014	Jan. 02, 2015
Segment Reporting Information [Line Items]
Segment revenue	$ 585.8	$ 642.2	$ 1,168.4	$ 1,246.9
Consolidated segment operating income	36.0	97.2	75.5	172.9
Depreciation expense			17.9	15.6
Accounts receivable	355.5		355.5		$ 362.0
Inventories	280.8		280.8		278.1
Goodwill	2,087.4		2,087.4		2,101.2
Engineering And Construction [Member]
Segment Reporting Information [Line Items]
Segment revenue	338.5	368.1	637.8	677.4
Accounts receivable	219.4		219.4		227.7
Inventories	196.0		196.0		185.2
Goodwill	1,154.3		1,154.3		1,186.0
Field Solutions [Member]
Segment Reporting Information [Line Items]
Segment revenue	87.1	114.4	202.4	252.6
Accounts receivable	48.3		48.3		51.6
Inventories	44.0		44.0		51.0
Goodwill	106.2		106.2		96.0
Mobile Solutions [Member]
Segment Reporting Information [Line Items]
Segment revenue	128.3	122.9	256.5	241.5
Accounts receivable	66.5		66.5		62.9
Inventories	24.2		24.2		26.1
Goodwill	804.7		804.7		796.0
Advanced Devices [Member]
Segment Reporting Information [Line Items]
Segment revenue	31.9	36.8	71.7	75.4
Accounts receivable	21.3		21.3		19.8
Inventories	16.6		16.6		15.8
Goodwill	22.2		22.2		$ 23.2
Operating Segments [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	115.4	169.6	228.7	313.9
Depreciation expense	5.3	4.8	10.6	9.5
Operating Segments [Member] \| Engineering And Construction [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	60.5	95.7	97.5	156.8
Depreciation expense	3.5	3.2	7.1	6.3
Operating Segments [Member] \| Field Solutions [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	24.9	39.6	65.5	93.3
Depreciation expense	0.3	0.2	0.6	0.4
Operating Segments [Member] \| Mobile Solutions [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	18.9	21.7	39.4	39.0
Depreciation expense	1.3	1.3	2.6	2.5
Operating Segments [Member] \| Advanced Devices [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	11.1	12.6	26.3	24.8
Depreciation expense	$ 0.2	$ 0.1	$ 0.3	$ 0.3

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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