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Number of warrants issued during the period pursuant to public offering.

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Amount of warrants issued during the period pursuant to public offering.

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- Definition

Number of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Amount of expense (income) related to adjustment to fair value of warrant liability.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 25
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e20148-110875

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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- Definition

Expected dividends to be paid to holders of the underlying shares or financial instruments (expressed as a percentage of the share or instrument's price).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Period the instrument, asset or liability is expected to be outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

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Risk-free interest rate assumption used in valuing an instrument.

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- Definition

Fair value portion of warrants not settleable in cash classified as equity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Estimated Fair Value of Financial Instruments - Warrant Liability (Details) - USD ($) shares in Thousands, $ in Thousands			3 Months Ended		12 Months Ended
	Feb. 10, 2017	Oct. 11, 2016	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Estimated Fair Value Level 2
Changes in fair market value of warrant liabilities			$ 1,218	$ (86,378)
Warrant liability
Number of Warrants
Warrants outstanding at beginning of year			450
Reclassification of warrant liability to equity (in shares)			(100)
Warrants outstanding at end of period			350		450
Warrant liability \| Level 2
Fair value assumptions for warrants
Risk-free interest rate	1.47%	0.87%	2.12%		1.95%
Expected remaining term	3 years	2 years	11 days		3 months 11 days
Expected volatility	71.42%	75.00%	60.00%		60.00%
Dividend yield	0.00%	0.00%	0.00%		0.00%
Estimated Fair Value Level 2
Fair value at beginning of year			$ 8,973
Warrants exercised			(1,776)
Changes in fair market value of warrant liabilities			(1,218)
Fair value at end of year			$ 5,979		$ 8,973
Warrant liability \| February 10, 2017 stock purchase agreement \| Level 2
Fair value assumptions for warrants
Risk-free interest rate						1.14%
Expected remaining term						6 months 4 days
Expected volatility						69.34%
Dividend yield						0.00%
Warrant liability \| October 11, 2016 public offering \| Level 2
Fair value assumptions for warrants
Risk-free interest rate						1.38%
Expected remaining term						1 year 3 months 10 days
Expected volatility						73.85%
Dividend yield						0.00%