Warrants (Warrants Classified as Equity) (Details) - $ / shares			12 Months Ended
Jul. 29, 2016	May 08, 2013	Dec. 31, 2016	Sep. 30, 2017	Jun. 28, 2016	May 10, 2016
Warrants and Rights Note Disclosure [Abstract]
Exercise price (usd per share)	$ 8.60	$ 49.40	$ 79.40	$ 79.40	$ 8.60	$ 30.20
Warrant term			5 years
Fair value assumptions, expected volatility rate	106.63%	75.34%	77.13%
Fair value assumptions, expected term (in years)	5 years 6 months	7 days	5 years 6 months
Fair value assumptions, risk free interest rate	1.35%	1.20%	1.26%
Fair value assumptions, expected dividend rate	0.00%	0.00%	0.00%
Warrants outstanding	50,000	9,109	100,000	15,000		50,000
Fair value of warrants granted (usd per share)		$ 38.60

Class of Warrant or Right, Term

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- Definition

Fair Value of Warrants Granted, per Share

+ References

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- Definition

Warrants Granted, Number of Shares

+ References

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- Definition

Exercise price per share or per unit 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)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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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).

+ References

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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- Definition

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.

+ References

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- Definition

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

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- Definition

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

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- References

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