SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Business Activities (Details) $ in Millions	6 Months Ended	12 Months Ended
	Dec. 31, 2022 USD ($) State Squarefeet	Dec. 31, 2022 USD ($) Segment Squarefeet State Campus School
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
Approximate area of leased school space | Squarefeet	55,000	55,000
Capital expenditures	$ 0.4	$ 0.4
Rent paid	$ 0.3	$ 0.3