Commitments and Contingencies - Warranty (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 28, 2014	Dec. 29, 2013
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Balance, at beginning of the period	$ 5.4us-gaap_ProductWarrantyAccrual	$ 5.2us-gaap_ProductWarrantyAccrual
Costs accrued and revenues deferred	0.4	1.2
Adjustments to preexisting warranties	(0.4)	(0.9)
Settlements made (in cash or kind) and revenues recognized	(0.1)	(0.1)
Balance, at end of period	5.3us-gaap_ProductWarrantyAccrual	5.4us-gaap_ProductWarrantyAccrual
Less: Non-Current portion	0.4	0.3
Current warranty liability	$ 4.9	$ 5.1
Minimum
Warranty Coverage Period [Line Items]
Warranty coverage period	1 year
Maximum
Warranty Coverage Period [Line Items]
Warranty coverage period	10 years
Product Warranties \| Minimum
Warranty Coverage Period [Line Items]
Warranty coverage period	1 year
Product Warranties \| Maximum
Warranty Coverage Period [Line Items]
Warranty coverage period	10 years

Product Warranty Accrual, Payments, Revenue Recognized, And Other

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- Definition

Product Warranty Accrual, Warranty Term

+ References

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.15(5))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

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-Paragraph 15

-Subparagraph 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

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-Section 50

-Paragraph 8

-Subparagraph ((c)(5))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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-Section S99

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-Subparagraph (SX 210.5-02.20)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 25

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6397716&loc=d3e11281-110244

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 7

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.24)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 24

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 3

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- Definition

Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(3))

-URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249

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- Definition

Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard product warranties (including adjustments related to changes in estimates). Does not include any Increase or Decrease in the liability for accruals related to extended product warranties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Subparagraph ((c)(4))

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