Defined Benefit Pension Plan - Additional information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Jun. 30, 2019
Defined Benefit Pension Plan
Consecutive period of employee's average month pay received to determine benefits under the Plan			5 years
Number of years of employment to determine pension benefit			10 years
Recognized pension income	$ 21,174	$ 25,422	$ 42,348	$ 63,555
Estimated amortizations from AOCI into net periodic pension cost during the next fiscal year					$ 215,747