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Schedule I - Valuation and Qualifying Accounts (Detail) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Allowance for Doubtful Accounts (Deducted from Accounts Receivable) [Member]    
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]    
Balance at Beginning of Period $ 2,145,599 $ 2,010,721
Charged to Costs and Expenses 5,206,423 692,460
Deductions 2,318,987 557,582
Balance at End of Period 5,033,035 2,145,599
Valuation Allowance for Deferred Tax Assets [Member]    
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]    
Balance at Beginning of Period 311,214 3,760,454
Charged to Costs and Expenses   87,665
Deductions 3,074 3,536,905
Balance at End of Period $ 308,140 $ 311,214