Debt (Schedule Of Short-Term And Long-Term Balances Of Term Loan) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022	Dec. 01, 2017
Debt Instrument [Line Items]
Total loan balance	$ 312,710	$ 314,779
Less unamortized loan origination costs	(5,281)	(6,672)
Net borrowings	307,429	308,107
Less short-term loan balance	(1,552)	(1,608)
Long-term loan balance	305,877	306,499
2.45% Sparkasse Zollernalb (KFW Loan 1)
Debt Instrument [Line Items]
Total loan balance	$ 117	296
Interest rate on amounts borrowed	2.45%
1.40% Sparkasse Zollernalb (KFW Loan 2)
Debt Instrument [Line Items]
Total loan balance	$ 530	733
Interest rate on amounts borrowed	1.40%
Term Loan balance
Debt Instrument [Line Items]
Total loan balance	$ 212,063	213,750	$ 225,000
Convertible Senior Notes
Debt Instrument [Line Items]
Total loan balance	$ 100,000	$ 100,000