Acquisitions - Pro Forma (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	9 Months Ended	12 Months Ended	9 Months Ended
Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014	Sep. 28, 2013	Sep. 27, 2014 Reznor [Member]	Sep. 28, 2013 Reznor [Member]	Dec. 31, 2013 Reznor [Member]	Sep. 28, 2013 2GIG Technologies, Inc. [Member]
Business Acquisition [Line Items]
Net sales					$ 1,961.4	$ 1,846.3	$ 2,447.1	$ 1,771.0
Operating earnings					26.6	82.4	100.6	89.1
Net earnings					(42.1)	(0.1)	(4.7)	7.4
Basic earnings (loss) per share (in dollars per share)					$ (2.70)	$ (0.01)	$ (0.31)	$ 0.48
Diluted earnings (loss) per share (in dollars per share)					$ (2.70)	$ (0.01)	$ (0.31)	$ 0.47
Depreciation & amortization expense					79.9	82.1	111.0	69.4
Impairment of long-lived assets and goodwill ($4.4 million)	0	0	80.4	0	80.4	0	0
Acquisition cost excluded from pro forma information								$ 1.8

Business Acquisition, Pro Forma Amortization and Depreciation Expense

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

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- Definition

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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- Definition

The pro forma income from continuing operations before changes in accounting and extraordinary items, net of tax effect, for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

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For transactions that are recognized separately from the acquisition of assets and assumptions of liabilities in the business combination, such as related to pre-existing relationships with the acquiree, this element represents the disclosure of the amount of acquisition related costs which have been expensed.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

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