SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) segments	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments | segments									3
Revenues									$ 226,970	$ 259,769	$ 262,615
Depreciation									9,849	9,298	10,944
Amortization of intangible assets									6,787	13,894	16,257
Operating income (loss)	$ 8,347	$ (16,083)	$ 8,485	$ 2,642	$ (24,279)	$ 10,958	$ 10,516	$ 9,160	3,391	6,355	46,604
Interest expense									(3,481)	(3,289)	(3,744)
Other expense									(29)	(25)	(11)
Income (loss) before income taxes									(119)	3,041	42,849
Capital expenditures									11,414	9,238	8,542
Assets	310,095				368,935				310,095	368,935	422,636
United States [Member]
Segment Reporting Information [Line Items]
Revenues									167,855	185,847	187,427
UNITED KINGDOM
Segment Reporting Information [Line Items]
Revenues									23,969	36,841	35,452
EMEA, APAC and Canada [Domain]
Segment Reporting Information [Line Items]
Revenues									35,146	37,081	39,736
Non-US [Member]
Segment Reporting Information [Line Items]
Revenues									59,115	73,922	75,188
Tech & Clearance [Member]
Segment Reporting Information [Line Items]
Revenues									135,455	140,414	136,596
Depreciation									6,565	6,495	6,280
Amortization of intangible assets									1,737	3,460	3,838
Operating income (loss)									51,667	53,897	51,088
Capital expenditures									7,047	5,652	5,611
Assets	179,985				177,519				179,985	177,519	185,547
Global Industry Group Segment [Member]
Segment Reporting Information [Line Items]
Revenues									63,604	78,283	84,556
Depreciation									891	915	1,017
Amortization of intangible assets									4,029	8,735	8,701
Operating income (loss)									(18,102)	(26,624)	12,708
Capital expenditures									1,166	1,028	870
Assets	98,821				150,111				98,821	150,111	189,980
Healthcare Segment [Member]
Segment Reporting Information [Line Items]
Revenues									27,066	25,877	23,123
Depreciation									2,089	1,599	2,639
Amortization of intangible assets									835	1,202	3,080
Operating income (loss)									(929)	(490)	(3,252)
Capital expenditures									1,113	2,350	1,548
Assets	14,375				18,134				14,375	18,134	19,558
Corporate & Other Segment [Member]
Segment Reporting Information [Line Items]
Revenues									845	15,195	18,340
Depreciation									304	289	1,008
Amortization of intangible assets									186	497	638
Operating income (loss)									(29,245)	(20,428)	(13,940)
Capital expenditures									2,088	208	513
Assets	$ 16,914				$ 23,171				$ 16,914	$ 23,171	$ 27,551