Pension and Profit Sharing - Benefit Obligation (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assumptions used to determine benefit obligation:
Discount rate		3.14%	3.40%
Changes in benefit obligation:
Benefit obligation at beginning of year	$ (1,362,867)	$ (1,499,798)	$ (1,776,788)
Interest cost		(48,161)	(55,811)
Service cost	(1,000)	(36,000)	(36,000)
Actuarial (loss) gain	$ (86,000)	(20,289)	99,019
Benefits and plan expenses paid		241,381	269,782
Benefit obligation at end of year		$ (1,362,867)	$ (1,499,798)