Warranties (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 29, 2015	Mar. 30, 2014
Product Warranties Disclosures [Abstract]
Warranty term, minimum	1 year
Warranty term, maximum	2 years
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance, beginning of fiscal year	$ 355us-gaap_StandardProductWarrantyAccrual	$ 379us-gaap_StandardProductWarrantyAccrual
Changes in product warranties charged to earnings	151	(19)
Use of reserve for warranty obligations	(131)	(36)
Balance, end of period	$ 375us-gaap_StandardProductWarrantyAccrual	$ 324us-gaap_StandardProductWarrantyAccrual

Standard Warranty Length, Maximum

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- Definition

Standard Warranty Length, Minimum

+ References

No definition available.

+ Details

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- Details

Name:	us-gaap_MovementInStandardProductWarrantyAccrualRollForward
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- Details

Name:	us-gaap_ProductWarrantiesDisclosuresAbstract
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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ 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)(1),(c)(5)

-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	credit
Period Type:	instant

- Definition

Represents the aggregate decrease in the liability for payments made (in cash or in kind) to satisfy claims under the terms of the standard product warranty. Does not include any Increase or Decrease in the liability for payments related to extended product warranties.

+ 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)(2))

-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Represents the aggregate increase in the liability for accruals related to standard product warranties issued during the reporting period. Does not include any increase 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

-Topic 460

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph ((c)(3))

-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

+ Details

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Balance Type:	credit
Period Type:	duration