Consolidated Statements of Stockholders' Deficit - USD ($)	Total	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss, Net
Common stock, shares outstanding, beginning at Dec. 31, 2018		5,872,552
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock issued (shares)		31,000
Warrants exercised (shares)		15,181
Common stock, shares outstanding, ending at Dec. 31, 2019	5,918,733	5,918,733
Beginning Balance, amount at Dec. 31, 2018	$ (10,765,901)	$ 5,873	$ 113,243,227	$ (122,119,899)	$ (1,895,102)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(1,751,954)			(1,751,954)
Restricted stock issued		31	(31)
Warrants exercised	0	(15)	(15)
Share-based compensation	32,280		32,280
Accretion of Series A redeemable convertible preferred stock	(389,811)		(389,811)
Dividends on Series A redeemable convertible preferred stock	(1,157,762)		(1,157,762)
Foreign currency translation	(4,921)				(4,921)
Net minimum pension liability	6,763				6,763
Ending Balance, amount at Dec. 31, 2019	$ (14,031,306)	$ 5,919	111,727,888	(123,871,853)	(1,893,260)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock issued (shares)		30,730
Common stock, shares outstanding, ending at Dec. 31, 2020	5,949,463	5,949,463
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 1,138,509			1,138,509
Restricted stock issued	0	$ 30	(30)
Share-based compensation	15,755		15,755
Accretion of Series A redeemable convertible preferred stock	(552,551)		(552,551)
Dividends on Series A redeemable convertible preferred stock	(1,083,892)		(1,083,892)
Foreign currency translation	(68,854)				(68,854)
Net minimum pension liability	(25,847)				(25,847)
Ending Balance, amount at Dec. 31, 2020	$ (14,608,186)	$ 5,949	$ 110,107,170	$ (122,733,344)	$ (1,987,961)