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Fair Value Measurements - Rollforward (Details) - USD ($)
3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning Balance $ 472,851 $ 483,804
Total income recognized in earnings (2,629) (2,752)
Ending Balance $ 470,222 $ 481,052