Note 3 - Revenue Recognition - Revenues Disaggregated by Revenue Source (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Revenues	$ 51,710	$ 45,512	$ 102,522	$ 91,853
Engineering Services [Member]
Revenues			42,988	39,810
Health Care [Member]
Revenues			45,492	34,876
Technology Service [Member]
Revenues			14,042	17,167
Time-and-materials Contract [Member] | Engineering Services [Member]
Revenues			38,460	34,078
Time-and-materials Contract [Member] | Health Care [Member]
Revenues			44,697	33,726
Time-and-materials Contract [Member] | Technology Service [Member]
Revenues			13,950	16,921
Fixed-price Contract [Member] | Engineering Services [Member]
Revenues			4,528	5,732
Permanent Placement Services [Member] | Health Care [Member]
Revenues			795	1,150
Permanent Placement Services [Member] | Technology Service [Member]
Revenues			$ 92	$ 246