DERIVATIVE FINANCIAL INSTRUMENTS - Narrative (Details) - contract
Mar. 31, 2022
Dec. 31, 2021
Dec. 31, 2020
Dec. 31, 2019
Derivatives, Fair Value [Line Items]        
Number of derivative instruments     0 0
Non-employee Warrants        
Derivatives, Fair Value [Line Items]        
Number of derivative instruments 19,122,000 19,122,000    
Non-employee Earnouts        
Derivatives, Fair Value [Line Items]        
Number of derivative instruments 7,655,000 7,655,000