Business Segments (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)
Segment Reporting [Abstract]
Number of reportable business segments \| segment	3
Segment Reporting Information [Line Items]
Revenue	$ 114,551	$ 128,281
Gross Profit	21,441	17,614
General and administrative expenses	14,836	17,284
Sales and marketing expenses	2,468	1,839
Restructuring charges	699	0
Operating income	3,169	(445)
Other income (expense)	823	500
Income before income tax expense	2,165	(1,923)
Gain on sale of business	$ 0	1,064
Number of reportable business segments \| segment	3
Managed Learning Services [Member]
Segment Reporting Information [Line Items]
Revenue	$ 40,472	42,047
Engineering and Technical Services [Member]
Segment Reporting Information [Line Items]
Revenue	51,420	57,317
Sales Enablement [Member]
Segment Reporting Information [Line Items]
Revenue	22,659	28,917
Manufacturing Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	18,660	21,503
Energy, Oil and Gas Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	8,607	8,051
Automotive Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	26,759	33,421
Financial and Insurance Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	19,598	20,458
Other Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	40,927	44,848
North America
Segment Reporting Information [Line Items]
Revenue	72,329	84,936
Gross Profit	14,493	13,058
North America \| Managed Learning Services [Member]
Segment Reporting Information [Line Items]
Revenue	22,656	24,000
North America \| Engineering and Technical Services [Member]
Segment Reporting Information [Line Items]
Revenue	33,202	39,897
North America \| Sales Enablement [Member]
Segment Reporting Information [Line Items]
Revenue	16,471	21,039
North America \| Manufacturing Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	17,521	19,849
North America \| Energy, Oil and Gas Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	6,922	6,986
North America \| Automotive Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	19,679	24,963
North America \| Financial and Insurance Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	9,306	9,692
North America \| Other Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	18,901	23,446
EMEA
Segment Reporting Information [Line Items]
Revenue	29,973	31,898
Gross Profit	5,050	3,776
EMEA \| Managed Learning Services [Member]
Segment Reporting Information [Line Items]
Revenue	10,689	12,935
EMEA \| Engineering and Technical Services [Member]
Segment Reporting Information [Line Items]
Revenue	18,029	17,305
EMEA \| Sales Enablement [Member]
Segment Reporting Information [Line Items]
Revenue	1,255	1,658
EMEA \| Manufacturing Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	1,139	1,654
EMEA \| Energy, Oil and Gas Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	1,514	778
EMEA \| Automotive Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	1,529	2,630
EMEA \| Financial and Insurance Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	6,484	7,402
EMEA \| Other Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	19,307	19,434
Emerging Markets
Segment Reporting Information [Line Items]
Revenue	12,249	11,447
Gross Profit	1,898	780
Emerging Markets \| Managed Learning Services [Member]
Segment Reporting Information [Line Items]
Revenue	7,127	5,112
Emerging Markets \| Engineering and Technical Services [Member]
Segment Reporting Information [Line Items]
Revenue	189	115
Emerging Markets \| Sales Enablement [Member]
Segment Reporting Information [Line Items]
Revenue	4,933	6,220
Emerging Markets \| Manufacturing Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	0	0
Emerging Markets \| Energy, Oil and Gas Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	171	287
Emerging Markets \| Automotive Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	5,551	5,828
Emerging Markets \| Financial and Insurance Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	3,808	3,364
Emerging Markets \| Other Market Sector [Member]
Segment Reporting Information [Line Items]
Revenue	2,719	1,968
Operating Segments
Segment Reporting Information [Line Items]
Revenue	114,551	128,281
Operating Segments \| North America
Segment Reporting Information [Line Items]
Revenue	72,329	84,936
Operating Segments \| EMEA
Segment Reporting Information [Line Items]
Revenue	29,973	31,898
Operating Segments \| Emerging Markets
Segment Reporting Information [Line Items]
Revenue	$ 12,249	$ 11,447

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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