REVENUE RECOGNITION (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Total revenues	$ 61,889	$ 65,279
Unearned tuition	20,890		$ 24,647
Contract liability	18,100
ASU 2016-10 [Member]
Disaggregation of Revenue [Line Items]
Unearned tuition	20,900		$ 24,600
Services Transferred at a Point in Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	2,783	2,532
Services Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	59,106	62,747
Transportation and Skilled Trades Segment [Member]
Disaggregation of Revenue [Line Items]
Total revenues	42,747	43,159
Transportation and Skilled Trades Segment [Member] | Services Transferred at a Point in Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	2,048	1,775
Transportation and Skilled Trades Segment [Member] | Services Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	40,699	41,384
Healthcare and Other Professions Segment [Member]
Disaggregation of Revenue [Line Items]
Total revenues	19,142	17,845
Healthcare and Other Professions Segment [Member] | Services Transferred at a Point in Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	735	764
Healthcare and Other Professions Segment [Member] | Services Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	18,407	17,081
Transitional Segment [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	4,275
Transitional Segment [Member] | Services Transferred at a Point in Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	0	(7)
Transitional Segment [Member] | Services Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Total revenues	$ 0	$ 4,282