GOODWILL AND OTHER INTANGIBLES (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2017	Dec. 31, 2016
Changes in Carrying Amount of Goodwill [Abstract]
Gross Goodwill Balance			$ 117,176	$ 117,176	$ 117,176
Accumulated Impairment Losses			93,881	102,640	102,640
Net Goodwill Balance			23,295	14,536	14,536
Impairment		$ 8,759
Adjustments	$ 0
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount, beginning balance	470	470
Additions		0
Gross carrying amount, ending balance		470	470
Accumulated amortization, beginning balance	438	420
Amortization		18
Accumulated amortization, ending balance		438	420
Net carrying amount at end of the period	16	32
Estimated future amortization expense [Abstract]
2018	16	32		16	32
Maximum [Member]
Finite-Lived Intangible Assets [Line Items]
Amortization	100	100	100
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount, beginning balance	310	310
Additions		0
Gross carrying amount, ending balance		310	310
Accumulated amortization, beginning balance	310	308
Amortization		2
Accumulated amortization, ending balance		310	308
Net carrying amount at end of the period		$ 2
Weighted average amortization period		7 years
Estimated future amortization expense [Abstract]
2018		$ 2			2
Curriculum [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount, beginning balance	160	160
Additions	0	0
Gross carrying amount, ending balance	160	160	160
Accumulated amortization, beginning balance	128	112
Amortization	16	16
Accumulated amortization, ending balance	144	128	$ 112
Net carrying amount at end of the period	$ 16	$ 32
Weighted average amortization period	10 years	10 years
Estimated future amortization expense [Abstract]
2018	$ 16	$ 32		$ 16	$ 32