Note 10 - Changes in Accrued Warranty (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 26, 2015	Dec. 27, 2014	Dec. 28, 2013
Beginning balance	$ 5,848	$ 4,673	$ 4,206
Warranty accruals	6,747	6,176	4,814
Warranty payments	$ (7,709)	$ (5,001)	(6,180)
Warranty liability assumed			1,833
Ending balance	$ 4,886	$ 5,848	$ 4,673

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.

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)(5))
-URI http://asc.fasb.org/extlink&oid=51674963&loc=d3e12565-110249

Reference 2: 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))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Total liability for standard and extended product warranties acquired in a business acquisition.

+ References

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.

+ References

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Balance Type:	debit
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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

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