Income Taxes (Details) - EUR (€)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Taxes
U.S. Federal statutory rates on net loss before income taxes	€ (993,000)	€ (868,000)	€ (879,000)
Effect of foreign statutory rate differences	(60,000)	(40,000)	(43,000)
Effect of exchange rate changes	(1,089,000)	1,275,000	39,000
Expiration of net operating loss carry forwards	217,000	123,000	200,000
Permanent differences	0	0	0
Change in valuation allowance	1,925,000	(465,000)	705,000
Income tax provision	€ 0	€ 25,000	€ 22,000