Merger with Macrocure and Related Transactions - Subscription Agreement (Details) - Subscription Agreement - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
Jan. 20, 2017	Dec. 31, 2017
Merger with Macrocure
Purchase price		$ 8,982
HCV IX
Merger with Macrocure
Issuance of stock (in shares)	1,010,225
Purchase price	$ 10,000
Price per common stock (in dollars per share)	$ 9.90

Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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