The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

+ References

No definition available.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

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- Definition

Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-SubTopic 15
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Derivative Financial Instruments - 6% Convertible Promissory Notes (Additional Information) (Details) - 6% Convertible Promissory Notes - Convertible promissory notes - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Jul. 01, 2017	Sep. 20, 2016	Sep. 10, 2016	Jan. 29, 2016	Dec. 15, 2015
Debt Instrument [Line Items]
Interest rate percentage	6.00%		6.00%		6.00%	6.00%
Debt face amount							$ 75,000,000	$ 75,000,000	$ 25,000,000	$ 160,000,000
Convertible stock price (in dollars per share)	$ 46.37		$ 46.37							$ 11.25
Convertible debt, stock price trigger			75.00%
Embedded derivative liability								$ 177,200,000
Gain (loss) on embedded derivative	$ 600,000	$ 100,000	$ (30,900,000)	$ 2,600,000