Business Segments (Schedule Of Reportable Segments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011	Dec. 31, 2011
Segment Reporting Information [Line Items]
External sales	$ 863.9	$ 681.8	$ 1,671.8	$ 1,344.4
Intersegment sales		0
Total sales	863.9	681.8	1,671.8	1,344.4
Segment income from operations	103.3	54.8	182.4	118.9
Identifiable assets	3,463.5	2,646.3	3,463.5	2,646.3	3,266.5
Depreciation and amortization	32.2	22.0	63.1	43.6
Electrical Segment [Member]
Segment Reporting Information [Line Items]
External sales	783.6	611.3	1,515.0	1,205.6
Intersegment sales	1.0	2.8	1.8	5.2
Total sales	784.6	614.1	1,516.8	1,210.8
Segment income from operations	91.5	44.9	160.9	100.4
Identifiable assets	3,251.4	2,510.4	3,251.4	2,510.4
Depreciation and amortization	29.1	20.1	57.5	40.6
Mechanical Segment [Member]
Segment Reporting Information [Line Items]
External sales	80.3	70.5	156.8	138.8
Intersegment sales	0.8	0.6	1.6	1.2
Total sales	81.1	71.1	158.4	140.0
Segment income from operations	11.8	9.9	21.5	18.5
Identifiable assets	212.1	135.9	212.1	135.9
Depreciation and amortization	3.1	1.9	5.6	3.0
Eliminations [Member]
Segment Reporting Information [Line Items]
External sales	0	0	0	0
Intersegment sales	(1.8)	(3.4)	(3.4)	(6.4)
Total sales	(1.8)	(3.4)	(3.4)
Segment income from operations	0	0	0	0
Identifiable assets	0	0	0	0
Depreciation and amortization	$ 0		$ 0	$ 0

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 7

-Section 03

-Paragraph 12

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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The net result for the period of deducting operating expenses from operating revenues.

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Amount of revenue from external customers for the reportable segment. Such disclosure is presented if the amount is: (a) included in the measure of segment profit or loss reviewed by the chief operating decision maker or (b) otherwise regularly provided to the chief operating decision maker, even if not included in that measure of segment profit or loss.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 131

-Paragraph 27

-Subparagraph a

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Amount of revenue from transactions with other operating segments of the same entity.

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-Name Statement of Financial Accounting Standard (FAS)

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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 03

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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