Condensed Consolidated Balance Sheets (Unaudited) (Parentheticals) - USD ($) $ in Thousands	Jul. 01, 2017	Dec. 31, 2016	Jul. 02, 2016
Property and equipment, accumulated depreciation	$ 170,785	$ 172,333	$ 183,829
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	15,000,000	15,000,000	15,000,000
Preferred stock, shares issued (in shares)	0	0	0
Preferred stock, shares outstanding (in shares)	0	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	50,000,000	50,000,000	50,000,000
Common stock, shares issued (in shares)	16,034,437	15,856,927	15,856,305
Common stock, shares outstanding (in shares)	16,034,437	15,856,927	15,856,305

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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