Revenue Recognition (Disaggregation Of Revenue) (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Total sources of revenue	$ 76,148	$ 53,771
Domestic Hospitals [Member]
Disaggregation of Revenue [Line Items]
Total sources of revenue	38,932	30,228
International Hospitals [Member]
Disaggregation of Revenue [Line Items]
Total sources of revenue	27,638	16,135
International Distributors [Member]
Disaggregation of Revenue [Line Items]
Total sources of revenue	9,504	7,244
CardioGenesis [Member]
Disaggregation of Revenue [Line Items]
Total sources of revenue	$ 74	$ 164