Going Concern [Line Items]

No definition available.

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- Definition

Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3521-108585

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- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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- Definition

The cash outflow for cost incurred directly with the issuance of an equity security.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 230
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- Definition

The cumulative amount of the reporting entity's undistributed earnings or deficit.

+ References

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- Definition

Cash received on stock transaction after deduction of issuance costs.

+ References

No definition available.

+ Details

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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Nature of Business and Going Concern - Additional Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands			3 Months Ended
	Dec. 12, 2017	Jun. 08, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Going Concern [Line Items]
Net Cash Provided by (Used in) Operating Activities			$ (1,727)	$ (675)
Retained Earnings (Accumulated Deficit)			(122,936)		$ (121,368)
Net Income (Loss) Attributable to Parent, Total			$ (1,568)	$ (806)
Private Placement [Member]
Going Concern [Line Items]
Sale of Stock, Number of Shares Issued in Transaction		1,900,000
Sale of Stock, Price Per Share		$ 4.00
Sale of Stock, Consideration Received on Transaction		$ 7,600
Payments of Stock Issuance Costs		$ 7,571
UnderwrittenPublicOfferingMember [Member]
Going Concern [Line Items]
Sale of Stock, Number of Shares Issued in Transaction	2,352,950
Sale of Stock, Price Per Share	$ 8.50
Sale of Stock, Consideration Received on Transaction	$ 21,200
Payments of Stock Issuance Costs	$ 19,810
Over-Allotment Option [Member]
Going Concern [Line Items]
Sale of Stock, Number of Shares Issued in Transaction	135,670