Number of shares issued for each share of convertible preferred stock that is converted.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (b)

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 14

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph (16)(c)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

-SubTopic 10

-Section S99

-Paragraph 3A

-Subparagraph 15

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 480

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-Section S99

-Paragraph 3A

-Subparagraph (12)(c)

-URI http://asc.fasb.org/extlink&oid=27011957&loc=SL6540498-122764

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The aggregate liquidation preference (or restrictions) of stock classified as temporary equity that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. 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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The maximum number of securities classified as temporary equity that are permitted to be issued by an entity's charter and bylaws. 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.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.27(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 28

-Subparagraph b

-Article 5

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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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The number of securities classified as temporary equity that have been issued and are held by the entity's shareholders. Securities outstanding equals securities issued minus 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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Schedule of Redeemable Preferred Stock (Detail) (USD $)	Sep. 30, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 29, 2012	Dec. 31, 2011	Jan. 31, 2013	Nov. 30, 2012	Nov. 30, 2013
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Preferred Shares Authorized	0us-gaap_TemporaryEquitySharesAuthorized	99,292,610us-gaap_TemporaryEquitySharesAuthorized	78,372,931us-gaap_TemporaryEquitySharesAuthorized
Preferred Shares Issued	0us-gaap_TemporaryEquitySharesIssued	94,483,404us-gaap_TemporaryEquitySharesIssued	73,991,017us-gaap_TemporaryEquitySharesIssued
Preferred Shares Outstanding	0	94,483,404	73,991,017
Liquidation Preference		$ 104,588,000	$ 63,629,000
Carrying Value		103,797	62,785
Common Stock Issuable Upon Conversion		15,045,125	11,782,007
Series A Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Preferred Shares Authorized		5,363,239	5,363,239
Preferred Shares Issued		5,363,239	5,363,239
Preferred Shares Outstanding		5,363,239	5,363,239
Liquidation Preference		2,250,000	2,250,000
Carrying Value		2,229	2,222
Common Stock Issuable Upon Conversion		854,018	854,018
Series B Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Preferred Shares Authorized		40,266,246	40,266,246
Preferred Shares Issued		40,266,246	40,266,246
Preferred Shares Outstanding		40,266,246	40,266,246
Liquidation Preference		30,402,000	30,402,000
Carrying Value		30,351	30,335
Common Stock Issuable Upon Conversion		6,411,822	6,411,822
Series C Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Preferred Shares Authorized		16,732,284	16,732,284
Preferred Shares Issued		16,732,284	16,732,284	7,808,400	8,923,884
Preferred Shares Outstanding		16,732,284	16,732,284
Liquidation Preference		15,161,000	15,161,000
Carrying Value		15,144	15,137
Common Stock Issuable Upon Conversion		2,664,376	2,664,376
Series D Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Preferred Shares Authorized		16,011,162	16,011,162
Preferred Shares Issued		16,011,162	11,629,248			4,381,914	6,653,988
Preferred Shares Outstanding		16,011,162	11,629,248
Liquidation Preference		21,775,000	15,816,000
Carrying Value		21,226	15,091
Common Stock Issuable Upon Conversion		2,549,548	1,851,791
Series E Preferred Stock [Member]
Schedule Of Redeemable Convertible Preferred Stock [Line Items]
Preferred Shares Authorized		20,919,679
Preferred Shares Issued		16,110,473						16,110,473
Preferred Shares Outstanding		16,110,473
Liquidation Preference		35,000,000
Carrying Value		$ 34,847
Common Stock Issuable Upon Conversion		2,565,361