The value of the financial instrument(s) that the original debt is being converted into in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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

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-Publisher FASB

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- Definition

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

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

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-Subparagraph (SX 210.5-02.22(a)(1))

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- Definition

Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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The cash inflow from issuance of callable preferred stock which is identified as being convertible to another type of financial security at the option of the issuer or the holder.

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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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-Paragraph 28

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- Definition

Debt Instrument Convertible Stock Price Trigger Percentage

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No definition available.

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Convertible Promissory Notes - Additional Information (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended		12 Months Ended			1 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Jan. 31, 2013	Nov. 30, 2012	Aug. 31, 2012
Debt Instrument [Line Items]
Promissory notes convertible threshold percentage of preferred stock price			90.00%
Number of redeemable convertible preferred stock issued	0us-gaap_TemporaryEquitySharesIssued		94,483,404us-gaap_TemporaryEquitySharesIssued	73,991,017us-gaap_TemporaryEquitySharesIssued
Proceeds from issuance of redeemable convertible preferred stock	$ 442	$ 5,955	$ 40,799	$ 16,057	$ 10,069
Series D Preferred Stock [Member]
Debt Instrument [Line Items]
Promissory notes principal amount							6,000
Number of redeemable convertible preferred stock issued			16,011,162	11,629,248		4,381,914	6,653,988
Proceeds from issuance of redeemable convertible preferred stock						5,956	9,044
Outstanding principal and accrued interest amount converted							6,086
Outstanding principal and accrued interest shares converted							4,975,260
Minimum [Member]
Debt Instrument [Line Items]
Proceeds from issuance of preferred stock			10,000
Convertible Notes Payable [Member]
Debt Instrument [Line Items]
Promissory notes principal amount							$ 6,000	$ 6,000
Annual interest rate			8.00%