Purchase of Comfortaire Acquired Intangible Assets (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended			9 Months Ended
Sep. 28, 2013	Sep. 29, 2012	Sep. 28, 2013 Comfortaire Corporation [Member]	Jan. 17, 2013 Comfortaire Corporation [Member]	Sep. 28, 2013 Comfortaire Corporation [Member] Developed Technologies[Member]	Sep. 28, 2013 Comfortaire Corporation [Member] Customer Relationships [Member]	Sep. 28, 2013 Comfortaire Corporation [Member] Trade Names/Trademarks [Member]
Estimated useful life definite-lived intangible asset					10 years	7 years
Acquired Definite-Lived Intangible Asset	$ 1,396	$ 0			$ 4,829	$ 2,413
Trade name/trademarks							1,396
Intangible assets			$ 8,638	$ 8,638

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16265-109275

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6910749&loc=d3e4845-128472

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, resulting from a business combination.

+ References

No definition available.

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- Definition

Amount of increase in assets, excluding financial assets and goodwill, lacking physical substance with an indefinite life, resulting from a business combination.

+ References

No definition available.

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