Disclosure About Fair Values of Assets and Liabilities - collateral-dependent impaired loans at fair value on a nonrecurring basis (Details) - Non recurring - Collateral-dependent impaired loans - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Carrying value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent impaired loans	$ 174,585	$ 51,568
Level 3 | Fair value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Collateral-dependent impaired loans	$ 174,585	$ 51,568