Business Segments (Schedule Of Reportable Segments) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Apr. 04, 2015 segment	Sep. 27, 2014 segment	Mar. 29, 2014	Jan. 03, 2015
Segment Reporting Information [Line Items]
External sales	$ 911.7us-gaap_Revenues		$ 801.2us-gaap_Revenues
Intersegment sales	0rbc_IntersegmentRevenue		0rbc_IntersegmentRevenue
Total sales	911.7us-gaap_SalesRevenueGoodsNet		801.2us-gaap_SalesRevenueGoodsNet
Gross profit	220.9us-gaap_GrossProfit		194.4us-gaap_GrossProfit
Operating Expenses	157.3us-gaap_OperatingExpenses		124.7us-gaap_OperatingExpenses
Income From Operations	63.6us-gaap_OperatingIncomeLoss		69.7us-gaap_OperatingIncomeLoss
Depreciation and amortization	35.9		32.8
Capital expenditures	21.2		22.3
Identifiable assets	4,967.5us-gaap_Assets		3,726.5us-gaap_Assets	3,407.6us-gaap_Assets
Number of reportable segments	3us-gaap_NumberOfReportableSegments	2us-gaap_NumberOfReportableSegments
Operating Segments \| Commercial and Industrial Systems
Segment Reporting Information [Line Items]
External sales	456.4		453.5
Intersegment sales	23.9		16.5
Total sales	480.3		470.0
Gross profit	112.9		115.7
Operating Expenses	79.6		78.5
Income From Operations	33.3		37.2
Depreciation and amortization	19.5		18.4
Capital expenditures	15.7		13.8
Identifiable assets	2,440.6		2,702.2
Operating Segments \| Climate Solutions
Segment Reporting Information [Line Items]
External sales	280.4		285.1
Intersegment sales	7.1		4.1
Total sales	287.5		289.2
Gross profit	63.7		62.7
Operating Expenses	30.3		36.4
Income From Operations	33.4		26.3
Depreciation and amortization	7.0		11.5
Capital expenditures	4.6		5.7
Identifiable assets	880.8		824.7
Operating Segments \| Power Transmission Solutions
Segment Reporting Information [Line Items]
External sales	174.9		62.6
Intersegment sales	1.1		1.0
Total sales	176.0		63.6
Gross profit	44.3		16.0
Operating Expenses	47.4		9.8
Income From Operations	(3.1)		6.2
Depreciation and amortization	9.4		2.9
Capital expenditures	0.9		2.8
Identifiable assets	1,646.1		199.6
Eliminations
Segment Reporting Information [Line Items]
External sales	0		0
Intersegment sales	(32.1)		(21.6)
Total sales	(32.1)		(21.6)
Gross profit	0		0
Operating Expenses	0		0
Income From Operations	0		0
Depreciation and amortization	0		0
Capital expenditures	0		0
Identifiable assets	$ 0		$ 0

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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.

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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.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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No definition available.

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- Definition

Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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

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