Pension and Profit Sharing - Benefit Obligation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assumptions used to determine benefit obligation:
Discount rate		3.87%	3.14%
Changes in benefit obligation:
Benefit obligation at beginning of year	$ (1,160,930)	$ (1,362,867)	$ (1,499,798)
Interest cost		(39,851)	(48,161)
Service cost	(543)	(33,000)	(36,000)
Actuarial gain (loss)	$ (87,000)	71,338	(20,289)
Benefits and plan expenses paid		203,450	241,381
Benefit obligation at end of year		$ (1,160,930)	$ (1,362,867)