Note 15 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016
Effective Income Tax Rate Reconciliation, Percent			37.90%	39.20%
Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability	$ 781		$ 781
Effective Income Tax Rate Reconciliation, Including Discrete Permanent Differences, Percent			55.70%
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Effective Income Tax Rate Reconciliation, Percent			41.60%	41.60%
Foreign Tax Authority [Member] | Canada Revenue Agency [Member]
Effective Income Tax Rate Reconciliation, Percent			26.50%	26.50%