SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Business Activities (Details)	12 Months Ended
Dec. 31, 2021 State School Segment Campus
Business Activities [Abstract]
Number of schools \| School	22
Number of states in which schools operate across the United States \| State	14
Number of campuses treated as destination schools \| Campus	5
Number of reportable segments \| Segment	2

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8672-108599

Name:	us-gaap_NumberOfReportableSegments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration