Note 14 - Segment Information - Revenue and Assets by Geographic Area (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues	$ 109,384	$ 102,343	$ 98,837
Long-lived assets	73,559	72,988	76,322
Total assets	120,624	128,049	129,510
UNITED STATES
Revenues	104,445	97,097	92,270
Long-lived assets	71,192	70,624	73,328
Total assets	106,288	115,480	115,730
CANADA
Revenues	4,939	5,246	6,567
Long-lived assets	2,367	2,364	2,994
Total assets	$ 14,336	$ 12,569	$ 13,780