Derivative warrant liability.

No definition available.

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- Definition

Represents the number of inputs used for valuation of warrants.

+ References

No definition available.

+ Details

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- Definition

The fair value allocated to warrants issued.

+ References

No definition available.

+ Details

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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.

+ Details

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- Details

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Fair Value Measurements - Additional Information (Detail) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) Input	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Nov. 30, 2017 USD ($)	Nov. 30, 2016 USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Number of inputs used for valuation of warrants \| Input			6
Derivative warrant liability [Abstract]
Change in fair value of the warrant liability, net	$ 14,697	$ 1,238	$ 15,103	$ 12,780	$ 564
Derivative warrant liabilities	4,169		$ 560	$ 18,751
Derivative warrant liabilities	$ 4,200
November 2017 Warrants [Member] \| Exchange Agreement [Member]
Derivative warrant liability [Abstract]
Value of warrants issued						$ 14,400	$ 14,400