Loans - Impairment Evaluation (Details) - USD ($)	12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2015
Allowance for loan losses:
Allowance for loans individually evaluated for impairment	$ 55,680	$ 52,803
Allowance for loans collectively evaluated for impairment	3,499,320	2,894,197
Total Allowance	3,555,000	2,947,000	$ 2,583,000
Loan balances
Loans individually evaluated for impairment	4,897,162	4,843,377
Loans collectively evaluated for impairment	234,555,766	195,851,060
Total loans	$ 239,452,928	$ 200,694,437
Allowance as percentage of loans:
Allowance as a percentage of loans individually evaluated for impairment	1.14%	1.09%
Allowance as a percentage of loans collectively evaluated for impairment	1.49%	1.48%
Allowance as a percentage of total loans evaluated for impairment	1.48%	1.47%
Commercial
Allowance for loan losses:
Allowance for loans individually evaluated for impairment	$ 6,487	$ 34,975
Allowance for loans collectively evaluated for impairment	1,696,513	1,302,025
Total Allowance	1,703,000	1,337,000	1,124,000
Loan balances
Loans individually evaluated for impairment	870,377	227,824
Loans collectively evaluated for impairment	106,078,606	82,826,781
Total loans	$ 106,948,983	$ 83,054,605
Allowance as percentage of loans:
Allowance as a percentage of loans individually evaluated for impairment	0.75%	15.35%
Allowance as a percentage of loans collectively evaluated for impairment	1.60%	1.57%
Allowance as a percentage of total loans evaluated for impairment	1.59%	1.61%
Agricultural
Allowance for loan losses:
Allowance for loans individually evaluated for impairment	$ 17,973
Allowance for loans collectively evaluated for impairment	900,027	$ 738,000
Total Allowance	918,000	738,000	697,000
Loan balances
Loans individually evaluated for impairment	864,357	885,757
Loans collectively evaluated for impairment	56,980,840	47,022,344
Total loans	$ 57,845,197	$ 47,908,101
Allowance as percentage of loans:
Allowance as a percentage of loans individually evaluated for impairment	2.08%
Allowance as a percentage of loans collectively evaluated for impairment	1.58%	1.57%
Allowance as a percentage of total loans evaluated for impairment	1.59%	1.54%
Residential
Allowance for loan losses:
Allowance for loans individually evaluated for impairment	$ 29,271	$ 17,828
Allowance for loans collectively evaluated for impairment	626,729	637,172
Total Allowance	656,000	655,000	644,000
Loan balances
Loans individually evaluated for impairment	3,142,020	3,726,602
Loans collectively evaluated for impairment	51,666,356	49,227,819
Total loans	$ 54,808,376	$ 52,954,421
Allowance as percentage of loans:
Allowance as a percentage of loans individually evaluated for impairment	0.93%	0.48%
Allowance as a percentage of loans collectively evaluated for impairment	1.21%	1.29%
Allowance as a percentage of total loans evaluated for impairment	1.20%	1.24%
Other
Allowance for loan losses:
Allowance for loans individually evaluated for impairment	$ 1,949
Allowance for loans collectively evaluated for impairment	276,051	$ 217,000
Total Allowance	278,000	217,000	$ 118,000
Loan balances
Loans individually evaluated for impairment	20,408	3,194
Loans collectively evaluated for impairment	19,829,964	16,774,116
Total loans	$ 19,850,372	$ 16,777,310
Allowance as percentage of loans:
Allowance as a percentage of loans individually evaluated for impairment	9.55%
Allowance as a percentage of loans collectively evaluated for impairment	1.39%	1.29%
Allowance as a percentage of total loans evaluated for impairment	1.40%	1.29%