For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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NATURE OF OPERATIONS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentrations of Credit Risk (Details) - Concentrations of Credit Risk - customer	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
One Customer \| Trade accounts receivable
Concentrations of Credit Risk
Number of customers	1	1
Percentage of concentration risk	13.40%	10.20%
One Customer \| Revenue.
Concentrations of Credit Risk
Number of customers	1
Percentage of concentration risk	10.40%
No Customer \| Revenue.
Concentrations of Credit Risk
Number of customers		0	0
Percentage of concentration risk		10.00%	10.00%