DESCRIPTION OF BUSINESS AND BASIS OF PRESENTATION (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) State	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) School State Campus Segment	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Business Activities [Abstract]
Number of schools | School			22
Number of states in which schools operate across the United States | State	14		14
Number of campuses treated as destination schools | Campus			5
Number of reportable segments | Segment			3
Liquidity [Abstract]
Cash, cash equivalents and restricted cash	$ 27,593	$ 15,754	$ 27,593	$ 15,754	$ 38,644	$ 45,946
Cash received under the Cares Act	11,500		11,500
Cash balance	9,900		9,900		$ 4,600
Cash deposit from Cares Act	11,500		11,500
Debt balance (excluding cash received from Cares Act)	1,500		1,500
Additional borrowing capacity	21,000		21,000
Income Taxes [Abstract]
Interest and penalties expense	$ 0	$ 0	$ 0	$ 0