Securities Registrations and Sales Agreements - Underwriting and Placement agency agreement (Details) - Laidlaw - Placement Agency Agreement - USD ($) $ / shares in Units, $ in Thousands	Nov. 14, 2017	Nov. 09, 2017
Issuance of stock (in shares)		61,333
Share price (in dollars per share)		$ 22.50
Net proceeds from sales of common stock	$ 1,082

Number of new stock issued during the period.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration