Segment and Enterprise Wide Disclosures	9 Months Ended
Dec. 31, 2018
Segment Reporting [Abstract]
Segment and Enterprise Wide Disclosures	Note 12. Segment and Enterprise Wide Disclosures The Company operates in one business segment—the research, development and sale of medical devices to assist or replace the pumping function of the failing heart. The Company’s chief operating decision maker (determined to be the Chief Executive Officer) does not manage any part of the Company separately, and the allocation of resources and assessment of performance are based on the Company’s consolidated operating results. International sales (sales outside the U.S., primarily in Germany and Japan) accounted for 14% and 13% of total revenue for the three and nine months ended December 31, 2018, respectively, and 11% of total revenue in each of the three and nine months ended December 31, 2017, respectively. The Company’s long-lived assets are located in the U.S. except for $41.7 million and $35.5 million at December 31, 2018 and March 31, 2018, respectively, which are located primarily in Germany.

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-URI http://asc.fasb.org/topic&trid=2134510

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