Accumulated Other Comprehensive Loss (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Other comprehensive (loss) income
Accumulated other comprehensive (loss) income, beginning balance			$ (21,702,577)
Total other comprehensive income (loss), net of applicable taxes:	$ 104,917	$ 63,122	(75,179)	$ (490,844)
Accumulated other comprehensive (loss) income, ending balance	(22,478,965)		(22,478,965)
Foreign Currency Translation
Other comprehensive (loss) income
Accumulated other comprehensive (loss) income, beginning balance	(2,046,484)	(2,288,570)	(1,866,388)	(1,726,994)
Other comprehensive (loss) income before reclassifications	104,917	59,527	(75,179)	(502,049)
Amounts reclassified from accumulated other comprehensive (loss) income	0	0	0	0
Total other comprehensive income (loss), net of applicable taxes:	104,917	59,527	(75,179)	(502,049)
Accumulated other comprehensive (loss) income, ending balance	(1,941,567)	(2,229,043)	(1,941,567)	(2,229,043)
Net Unrealized Gains (Losses) on Marketable Securities
Other comprehensive (loss) income
Accumulated other comprehensive (loss) income, beginning balance	0	350	0	(3,406)
Other comprehensive (loss) income before reclassifications	0	(1,289)	0	1,224
Amounts reclassified from accumulated other comprehensive (loss) income	0	1,010	0	2,253
Total other comprehensive income (loss), net of applicable taxes:	0	(279)	0	3,477
Accumulated other comprehensive (loss) income, ending balance	0	71	0	71
Net Minimum Pension Liability
Other comprehensive (loss) income
Accumulated other comprehensive (loss) income, beginning balance	28,675	31,040	28,675	27,186
Other comprehensive (loss) income before reclassifications	0	2,616	0	4,039
Amounts reclassified from accumulated other comprehensive (loss) income	0	1,258	0	3,689
Total other comprehensive income (loss), net of applicable taxes:	0	3,874	0	7,728
Accumulated other comprehensive (loss) income, ending balance	28,675	34,914	28,675	34,914
Accumulated Other Comprehensive loss, net
Other comprehensive (loss) income
Accumulated other comprehensive (loss) income, beginning balance	(2,017,809)	(2,257,180)	(1,837,713)	(1,703,214)
Other comprehensive (loss) income before reclassifications	104,917	60,854	(75,179)	(496,786)
Amounts reclassified from accumulated other comprehensive (loss) income	0	2,268	0	5,942
Total other comprehensive income (loss), net of applicable taxes:	104,917	63,122	(75,179)	(490,844)
Accumulated other comprehensive (loss) income, ending balance	$ (1,912,892)	$ (2,194,058)	$ (1,912,892)	$ (2,194,058)