ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Fair value measurements on recurring and nonrecurring valuation techniques (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Contingent Consideration [Member] | Measurement Input, Price Volatility [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Assumptions Measurement Rate	20.80%	20.80%
Contingent Consideration [Member] | Measurement Input, Discount Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Assumptions Measurement Rate	14.50%	14.50%
Employment Agreement Award [Member] | Measurement Input, Discount Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Assumptions Measurement Rate	10.00%	10.00%
Employment Agreement Award [Member] | Measurement Input, Long-term Revenue Growth Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Assumptions Measurement Rate	2.00%	2.00%
Redeemable Noncontrolling Interest [Member] | Measurement Input, Discount Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Assumptions Measurement Rate	11.00%	11.00%
Redeemable Noncontrolling Interest [Member] | Measurement Input, Long-term Revenue Growth Rate [Member]
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Fair Value Assumptions Measurement Rate	1.00%	1.00%