FAIR VALUE MEASUREMENTS - Schedule of Key Assumptions (Details)	6 Months Ended
	Jun. 30, 2021
Valuation, Market Approach | Level 3 | Revenue volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration measurement input	0.150
Valuation, Market Approach | Level 3 | Revenue discount rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration measurement input	0.032
Valuation, Market Approach | Level 3 | Weighted average cost of capital
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration measurement input	0.125
Valuation, Market Approach | Level 3 | Common stock volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration measurement input	0.790
Valuation, Market Approach | Level 3 | Portion to be paid in cash
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Contingent consideration measurement input	0.300
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Percentage of anniversary payments made in cash (at least)	30.00%