Principal amount of debt redeemed.

No definition available.

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- Definition

Carrying value as of the balance sheet date of the portion of long-term debt due within one year or the operating cycle if longer identified as Convertible Notes Payable. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

+ References

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- Definition

Amount of a favorable spread to a debt holder between the amount of debt being converted and the value of the securities received upon conversion. This is an embedded conversion feature of convertible debt issued that is in-the-money at the commitment date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21538-112644

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6928298&loc=SL6031898-161870

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- Definition

Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

+ References

No definition available.

+ Details

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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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

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

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Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount, after accumulated amortization, of debt discount.

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-SubTopic 30
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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.8)
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- Definition

The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents the amount of short-term debt existing as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The gross value of stock issued during the period upon the conversion of convertible securities.

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Redeemable Convertible Notes - Additional Information (Detail)		12 Months Ended
	Feb. 19, 2018 USD ($)	Dec. 31, 2017 USD ($) d $ / shares	Dec. 31, 2016 USD ($)	Feb. 20, 2018 USD ($)	Aug. 19, 2015 USD ($)
Debt Instrument [Line Items]
Redeemable convertible notes, outstanding balance		$ 5,085,000	$ 19,403,000
Conversion of convertible notes in to common stock, value			1,000
Gain on extinguishment of redeemable convertible notes		0	99,000
Redeemable convertible notes, redeemed during period		$ 14,318,000	14,340,000
Subsequent Event
Debt Instrument [Line Items]
Redeemable convertible notes, outstanding balance				$ 0
Convertible Notes
Debt Instrument [Line Items]
Convertible notes, total outstanding principal amount					$ 37,000,000
Redeemable convertible notes, conversion per share price \| $ / shares		$ 137.85
Convertible notes, maturity date		Feb. 19, 2018
Convertible notes, maturity period		30 months
Redeemable convertible notes, threshold trading days \| d		10
Redeemable convertible notes, conversion feature		$ 1,500,000
Redeemable convertible notes, estimated fair value		37,100,000
Redeemable convertible notes, debt discount		1,400,000
Redeemable convertible notes, interest expense		0	$ 0
Redeemable convertible notes, redeemed		31,600,000
Conversion of convertible notes in to common stock, value		300,000
Redeemable convertible notes, redeemed during period		$ 14,300,000
Convertible Notes \| Subsequent Event
Debt Instrument [Line Items]
Convertible notes, maturity date	Feb. 19, 2018
Redeemable convertible notes, outstanding balance	$ 0
Convertible Notes \| After Reverse Stock Split
Debt Instrument [Line Items]
Redeemable convertible notes, conversion per share price \| $ / shares		$ 137.85