Loans and Allowance for Loan Losses - Allowance for loan losses activity and recorded investment in loan by segment (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Allowance for loan losses:
Balance, beginning of period	$ 1,405,072	$ 1,360,072
Provision (credit) charged to expense	25,000	45,000
Losses charged off	(22,527)	0
Recoveries	0	0
Balance, end of period	1,407,545	1,405,072
Ending balance: Individually evaluated for impairment	28,735	42,738
Ending balance: Collectively evaluated for impairment	1,378,810	1,362,334
Loans:
Ending balance	181,551,161	173,852,016
Ending balance: Individually evaluated for impairment	2,521,067	2,487,542
Ending balance: Collectively evaluated for impairment	179,030,094	171,364,474
One- to Four- Family Mortgage Loans Owner Occupied [Member]
Allowance for loan losses:
Balance, beginning of period	456,630	338,697
Provision (credit) charged to expense	(117,552)	117,933
Losses charged off	(14,431)	0
Recoveries	0	0
Balance, end of period	324,647	456,630
Ending balance: Individually evaluated for impairment	20,722	0
Ending balance: Collectively evaluated for impairment	303,925	456,630
Loans:
Ending balance	91,919,064	93,659,520
Ending balance: Individually evaluated for impairment	1,115,573	966,592
Ending balance: Collectively evaluated for impairment	90,803,491	92,692,928
One To Four Family Investment Mortgage Loans [Member]
Allowance for loan losses:
Balance, beginning of period	123,017	171,674
Provision (credit) charged to expense	(32,786)	(48,657)
Losses charged off	(8,012)	0
Recoveries	0	0
Balance, end of period	82,219	123,017
Ending balance: Individually evaluated for impairment	8,013	33,683
Ending balance: Collectively evaluated for impairment	74,206	89,334
Loans:
Ending balance	12,846,342	14,242,563
Ending balance: Individually evaluated for impairment	760,733	699,630
Ending balance: Collectively evaluated for impairment	12,085,609	13,542,933
Multi-Family Mortgage Loans [Member]
Allowance for loan losses:
Balance, beginning of period	224,384	240,896
Provision (credit) charged to expense	299,799	(16,512)
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	524,183	224,384
Ending balance: Individually evaluated for impairment	0	9,055
Ending balance: Collectively evaluated for impairment	524,183	215,329
Loans:
Ending balance	36,628,238	27,140,014
Ending balance: Individually evaluated for impairment	507,066	621,757
Ending balance: Collectively evaluated for impairment	36,121,172	26,518,257
Nonresidential Mortgage Loans [Member]
Allowance for loan losses:
Balance, beginning of period	182,338	196,811
Provision (credit) charged to expense	94,688	(14,473)
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	277,026	182,338
Ending balance: Individually evaluated for impairment	0	0
Ending balance: Collectively evaluated for impairment	277,026	182,338
Loans:
Ending balance	23,377,598	18,930,426
Ending balance: Individually evaluated for impairment	56,190	151,096
Ending balance: Collectively evaluated for impairment	23,321,408	18,779,330
Construction & Land Loans [Member]
Allowance for loan losses:
Balance, beginning of period	100,187	82,669
Provision (credit) charged to expense	(30,730)	17,518
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	69,457	100,187
Ending balance: Individually evaluated for impairment	0	0
Ending balance: Collectively evaluated for impairment	69,457	100,187
Loans:
Ending balance	5,329,188	7,293,737
Ending balance: Individually evaluated for impairment	0	0
Ending balance: Collectively evaluated for impairment	5,329,188	7,293,737
Real Estate Secured Lines of Credit [Member]
Allowance for loan losses:
Balance, beginning of period	296,873	312,638
Provision (credit) charged to expense	(191,686)	(15,765)
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	105,187	296,873
Ending balance: Individually evaluated for impairment	0	0
Ending balance: Collectively evaluated for impairment	105,187	296,873
Loans:
Ending balance	10,029,917	11,373,975
Ending balance: Individually evaluated for impairment	81,505	48,467
Ending balance: Collectively evaluated for impairment	9,948,412	11,325,508
Commercial Loans [Member]
Allowance for loan losses:
Balance, beginning of period	9,001	6,934
Provision (credit) charged to expense	2,407	2,067
Losses charged off	0	0
Recoveries	0	0
Balance, end of period	11,408	9,001
Ending balance: Individually evaluated for impairment	0	0
Ending balance: Collectively evaluated for impairment	11,408	9,001
Loans:
Ending balance	557,268	415,730
Ending balance: Individually evaluated for impairment	0	0
Ending balance: Collectively evaluated for impairment	557,268	415,730
Other Consumer Loans [Member]
Allowance for loan losses:
Balance, beginning of period	12,642	9,753
Provision (credit) charged to expense	860	2,889
Losses charged off	(84)	0
Recoveries	0	0
Balance, end of period	13,418	12,642
Ending balance: Individually evaluated for impairment	0	0
Ending balance: Collectively evaluated for impairment	13,418	12,642
Loans:
Ending balance	863,546	796,051
Ending balance: Individually evaluated for impairment	0	0
Ending balance: Collectively evaluated for impairment	$ 863,546	$ 796,051