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Fair Value Measurements - Rollforward (Details) - USD ($)
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning Balance $ 483,804 $ 498,086
Total income recognized in earnings (2,752) (5,759)
Ending Balance $ 481,052 $ 492,327