Summary of Significant Accounting Policies (Reconciliation of the Level 3 Warrant Liability Measured and Recorded at Fair Value on a Recurring Basis) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2018 USD ($)
Summary of Significant Accounting Policies [Abstract]
Balance as of January 1, 2018	$ 784
Fair value of warrants issued during period	2,906
Change in fair value of warrant liability, net	(387)
Balance as of September 30, 2018	$ 3,303

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Change in Fair Value

No definition available.

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- References

No definition available.

+ Details

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- Definition

Amount of issuances of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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