SUMMARY OF CRITICAL ACCOUNTING POLICIES AND ESTIMATES - Narrative (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2021
New Accounting Pronouncements or Change in Accounting Principle
Asset impairment	$ 0	$ 0
Common Class B and Class A
New Accounting Pronouncements or Change in Accounting Principle
Annual return (as a percent)		22.50%
Percentage of aggregate capital investment to be added to original per-unit price to determine cash purchase price (as a percent)		50.00%