Post-employment Benefit Obligations (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Austria
Post-employment Benefit Obligations
Employer monthly contribution (as a percent)	1.53%	1.53%	1.53%
Contribution costs	$ 56,000	$ 57,000	$ 68,000
U.S.
Post-employment Benefit Obligations
Contribution costs	$ 360,000	$ 396,000	$ 710,000
Percent of match, first level	100.00%	100.00%	100.00%
Employee voluntary contribution, first level	3.00%	3.00%	3.00%
Percent match, second level	50.00%	50.00%	50.00%
Employee voluntary contribution, second level	2.00%	2.00%	2.00%