FAIR VALUE - Summary of assets measured at fair value on a recurring basis (Detail) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale	$ 11,581,122	$ 11,870,508
MBSs - residential
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale	5,180,387	5,471,452
Fair Value, Recurring Basis | Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale	11,581,122	11,870,508
Fair Value, Recurring Basis | Corporate Bonds | Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale	6,400,735	6,399,056
Fair Value, Recurring Basis | MBSs - residential | Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale	5,180,387	5,471,452
Fair Value, Recurring Basis | Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale	11,581,122	11,870,508
Fair Value, Recurring Basis | Carrying Value | Corporate Bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale	6,400,735	6,399,056
Fair Value, Recurring Basis | Carrying Value | MBSs - residential
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Securities available for sale	$ 5,180,387	$ 5,471,452