Escrowed Cash - Schedule of Escrowed Cash Restricted (Detail) - USD ($)	Dec. 31, 2020	Dec. 31, 2019
Restricted Cash and Cash Equivalents Items [Line Items]
Net Escrowed cash restricted	$ 977,391	$ 1,124,074
Interest-Bearing Deposits [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Net Escrowed cash restricted	963,970	1,108,892
Security Deposit [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Net Escrowed cash restricted	$ 13,421	$ 15,182