Revenue Recognition (Disaggregation Of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Total sources of revenue	$ 67,505	$ 61,948
Domestic Hospitals [Member]
Disaggregation of Revenue [Line Items]
Total sources of revenue	35,611	33,543
International Hospitals [Member]
Disaggregation of Revenue [Line Items]
Total sources of revenue	20,570	19,008
International Distributors [Member]
Disaggregation of Revenue [Line Items]
Total sources of revenue	9,610	8,052
CardioGenesis Cardiac Laser Therapy [Member]
Disaggregation of Revenue [Line Items]
Total sources of revenue	$ 1,714	$ 1,345

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130543-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130539-203045

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130545-203045

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration