Number of new stock issued during the period.

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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Name:	us-gaap_StockIssuedDuringPeriodSharesNewIssues
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Nature of Business - Liquidity - Underwritten Public Offering (Details) - USD ($) $ in Millions	Nov. 14, 2017	May 17, 2017	Apr. 26, 2017
The Offering
Subsidiary, Sale of Stock [Line Items]
Issuance of stock (in shares)	61,333		165,079
Net proceeds from sales of common stock	$ 1.1	$ 5.3
Underwriter's option \| Laidlaw \| Maximum
Subsidiary, Sale of Stock [Line Items]
Issuance of stock (in shares)		24,239