REVENUE RECOGNITION (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Disaggregation of Revenue [Abstract]
Total revenues	$ 70,078	$ 67,308	$ 193,087	$ 194,452
Unearned tuition	21,525		21,525		$ 24,647
Revenue recognized included in contract liability	300		23,500
ASU 2016-10 [Member]
Disaggregation of Revenue [Abstract]
Unearned tuition	21,500		21,500		$ 24,600
Services Transferred at a Point in Time [Member]
Disaggregation of Revenue [Abstract]
Total revenues	5,732	4,779	11,128	9,382
Services Transferred over Time [Member]
Disaggregation of Revenue [Abstract]
Total revenues	64,346	62,529	181,959	185,070
Transportation and Skilled Trades Segment [Member]
Disaggregation of Revenue [Abstract]
Total revenues	51,006	48,795	135,838	134,284
Transportation and Skilled Trades Segment [Member] | Services Transferred at a Point in Time [Member]
Disaggregation of Revenue [Abstract]
Total revenues	4,514	3,799	8,219	7,173
Transportation and Skilled Trades Segment [Member] | Services Transferred over Time [Member]
Disaggregation of Revenue [Abstract]
Total revenues	46,492	44,996	127,619	127,111
Healthcare and Other Professions Segment [Member]
Disaggregation of Revenue [Abstract]
Total revenues	18,251	15,890	52,554	46,470
Healthcare and Other Professions Segment [Member] | Services Transferred at a Point in Time [Member]
Disaggregation of Revenue [Abstract]
Total revenues	1,162	902	2,847	2,199
Healthcare and Other Professions Segment [Member] | Services Transferred over Time [Member]
Disaggregation of Revenue [Abstract]
Total revenues	17,089	14,988	49,707	44,271
Transitional Segment [Member]
Disaggregation of Revenue [Abstract]
Total revenues	821	2,623	4,695	13,698
Transitional Segment [Member] | Services Transferred at a Point in Time [Member]
Disaggregation of Revenue [Abstract]
Total revenues	56	78	62	10
Transitional Segment [Member] | Services Transferred over Time [Member]
Disaggregation of Revenue [Abstract]
Total revenues	$ 765	$ 2,545	$ 4,633	$ 13,688