Financial Instruments (Summary Of Financial Instruments Measured At Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	$ 10,965	$ 12,439
Current contingent consideration	(16,800)	(16,430)
Long-term contingent consideration	(44,100)	(43,500)
Total liabilities	(60,900)	(59,930)
Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	10,006	11,484
Restricted securities	550	546
Endospan Loan [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loan	409	409
Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	10,556	12,030
Level 1 [Member] | Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents	10,006	11,484
Restricted securities	550	546
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets
Current contingent consideration
Long-term contingent consideration
Total liabilities
Level 2 [Member] | Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents
Restricted securities
Level 2 [Member] | Endospan Loan [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loan
Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total assets	409	409
Current contingent consideration	(16,800)	(16,430)
Long-term contingent consideration	(44,100)	(43,500)
Total liabilities	(60,900)	(59,930)
Level 3 [Member] | Money Market Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash equivalents
Restricted securities
Level 3 [Member] | Endospan Loan [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Loan	$ 409	$ 409