Segment Information (Schedule Of Revenue, Operating Income And Identifiable Assets By Segment) (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
Apr. 03, 2015	Apr. 04, 2014	Jan. 02, 2015
Segment Reporting Information [Line Items]
Segment revenue	$ 582.6us-gaap_Revenues	$ 604.7us-gaap_Revenues
Consolidated segment operating income	39.5us-gaap_OperatingIncomeLoss	75.7us-gaap_OperatingIncomeLoss
Depreciation expense	8.7us-gaap_Depreciation	7.5us-gaap_Depreciation
Accounts receivable	383.0us-gaap_AccountsReceivableNetCurrent		362.0us-gaap_AccountsReceivableNetCurrent
Inventories	276.0us-gaap_InventoryNet		278.1us-gaap_InventoryNet
Goodwill	2,059.4us-gaap_Goodwill		2,101.2us-gaap_Goodwill
Engineering And Construction [Member]
Segment Reporting Information [Line Items]
Segment revenue	299.3	309.3
Accounts receivable	218.7		227.7
Inventories	192.8		185.2
Goodwill	1,140.5		1,186.0
Field Solutions [Member]
Segment Reporting Information [Line Items]
Segment revenue	115.3	138.2
Accounts receivable	71.8		51.6
Inventories	44.2		51.0
Goodwill	94.3		96.0
Mobile Solutions [Member]
Segment Reporting Information [Line Items]
Segment revenue	128.2	118.6
Accounts receivable	65.7		62.9
Inventories	15.3		26.1
Goodwill	802.5		796.0
Advanced Devices [Member]
Segment Reporting Information [Line Items]
Segment revenue	39.8	38.6
Accounts receivable	26.8		19.8
Inventories	23.7		15.8
Goodwill	22.1		23.2
Operating Segments [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	113.3	144.3
Depreciation expense	5.3	4.7
Operating Segments [Member] \| Engineering And Construction [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	37.0	61.1
Depreciation expense	3.6	3.1
Operating Segments [Member] \| Field Solutions [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	40.6	53.7
Depreciation expense	0.3	0.2
Operating Segments [Member] \| Mobile Solutions [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	20.5	17.3
Depreciation expense	1.3	1.2
Operating Segments [Member] \| Advanced Devices [Member]
Segment Reporting Information [Line Items]
Consolidated segment operating income	15.2	12.2
Depreciation expense	$ 0.1	$ 0.2

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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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