Comprehensive Income - Accumulated Other Comprehensive (Loss) Income (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Accumulated other comprehensive income (loss), beginning balance	$ (1,633,999)	$ (2,336,201)
Change in net prior service credit and actuarial losses, net of tax	37,388	87,461
Translation adjustment	(461,374)	614,741
Accumulated other comprehensive income (loss), ending balance	(2,057,985)	(1,633,999)
Foreign Currency Translation Adjustment
Accumulated other comprehensive income (loss), beginning balance	(1,057,447)	(1,672,188)
Translation adjustment	(461,374)	614,741
Accumulated other comprehensive income (loss), ending balance	(1,518,821)	(1,057,447)
Net Prior Service Credit and Actuarial Losses
Accumulated other comprehensive income (loss), beginning balance	(576,551)	(664,012)
Change in net prior service credit and actuarial losses, net of tax	37,388	87,461
Accumulated other comprehensive income (loss), ending balance	$ (539,163)	$ (576,551)