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Reporting Segments (Details) - USD ($) $ in Thousands	3 Months Ended								9 Months Ended	12 Months Ended
Reporting Segments (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Revenue	$ 183,890	$ 220,260	$ 226,693	$ 233,524	$ 236,553	$ 244,662	$ 246,821	$ 257,458		$ 864,367	$ 985,494	$ 1,122,972
Gross profit	36,217	40,533	42,095	43,275	44,657	46,827	46,647	46,770		162,120	184,901	206,557
Operating profit (loss)	(2,281)	(17,921)	(6,460)	(3,821)	(8,810)	(22,129)	1,203	1,140		(30,483)	(28,596)	5,386
Other income (expense), net										(988)	61	(228)
Income (loss) before income taxes										(31,471)	(28,535)	5,158
Loss on disposition of business interests	0	11,301	0	0	0	0	0	310		11,301	310	0
Impairment					0	21,537	0	0		0	21,537	14,653
Restructuring Charges	$ 0	$ 3,478	$ 240	$ 49	$ 3,604	$ 566	$ 0	$ 47		3,767	4,217	3,645
Enterprise Talent [Member]
Segment Reporting Information [Line Items]
Revenue										495,955	595,963	728,686
Gross profit										56,362	71,928	88,738
Operating profit (loss)										(7,504)	(1,448)	24,594
Restructuring Charges										433	1,084	1,001
Specialty Talent and Technology Solutions [Member]
Segment Reporting Information [Line Items]
Revenue										74,931	41,430	32,145
Gross profit										22,108	13,432	10,920
Operating profit (loss)										(483)	731	4,053
Restructuring Charges										215	130	152
Engineering Solutions [Member]
Segment Reporting Information [Line Items]
Revenue										243,298	294,941	303,237
Gross profit										59,210	73,391	79,184
Operating profit (loss)										(10,238)	(12,840)	(12,309)
Restructuring Charges										2,690	2,153	2,092
MRI [Member]
Segment Reporting Information [Line Items]
Revenue										50,183	53,160	58,904
Gross profit										24,440	26,150	27,715
Operating profit (loss)										3,980	6,012	6,531
Restructuring Charges										206	0	259
Corporate [Member]
Segment Reporting Information [Line Items]
Operating profit (loss)										(16,238)	(21,051)	(17,483)
Restructuring Charges										$ 223	$ 850	$ 141
Sales [Member] \| IBM [Member]
Segment Reporting Information [Line Items]
Concentration risk percentage										14.00%	15.00%	15.00%
CDI AndersElite Limited Disposition [Member] \| Disposed of by Sale [Member] \| Enterprise Talent [Member]
Segment Reporting Information [Line Items]
Loss on disposition of business interests									$ 11,300
Revenue										$ 59,302	$ 104,977	$ 113,691
Gross profit										9,758	17,579	19,121
Operating and administrative expenses										11,542	19,503	18,716
Impairment										0	10,653	0
Operating income (loss)										$ (1,784)	$ (12,577)	$ 405