v2.4.0.8

Redeemable Convertible Preferred Stock and Shareholders' Equity (Deficit) - Summary of Redeemable Convertible Preferred Stock (Detail) (USD $) In Thousands, except Share data, unless otherwise specified | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2013 | Sep. 30, 2012 | Dec. 31, 2012 | Dec. 31, 2011
Temporary Equity [Line Items] |  |  |  |
Accretion of dividends | $ 18,391 | $ 16,291 | $ 21,994 | $ 13,868
Series A Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 1,358 | 802 | 802 | 802
Issuance of shares |  |  |  |
Accretion of dividends | 52 |  | 556 |
Stock issuance costs |  |  |  |
Conversion to common stock | (1,410) |  |  |
Settlement of fractional shares upon conversion to common stock |  |  |  |
Ending Balance |  |  | 1,358 | 802
Beginning Balance, Shares | 705,400 | 705,400 | 705,400 | 705,400
Issuance of shares, Shares |  |  |  |
Conversion to common stock, Shares | (705,400) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 705,400 | 705,400
Series B Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 669 | 639 | 639 | 609
Issuance of shares |  |  |  |
Accretion of dividends | 19 |  | 30 | 30
Stock issuance costs |  |  |  |
Conversion to common stock | (688) |  |  |
Settlement of fractional shares upon conversion to common stock |  |  |  |
Ending Balance |  |  | 669 | 639
Beginning Balance, Shares | 694,000 | 694,000 | 694,000 | 694,000
Issuance of shares, Shares |  |  |  |
Conversion to common stock, Shares | (694,000) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 694,000 | 694,000
Series B-1 Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 1,360 | 1,300 | 1,300 | 1,240
Issuance of shares |  |  |  |
Accretion of dividends | 37 |  | 60 | 60
Stock issuance costs |  |  |  |
Conversion to common stock | (1,397) |  |  |
Settlement of fractional shares upon conversion to common stock |  |  |  |
Ending Balance |  |  | 1,360 | 1,300
Beginning Balance, Shares | 1,212,360 | 1,212,360 | 1,212,360 | 1,212,360
Issuance of shares, Shares |  |  |  |
Conversion to common stock, Shares | (1,212,360) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 1,212,360 | 1,212,360
Series C Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 7,134 | 6,729 | 6,729 | 6,346
Issuance of shares |  |  |  |
Accretion of dividends | 266 |  | 405 | 383
Stock issuance costs |  |  |  |
Conversion to common stock | (7,400) |  |  |
Settlement of fractional shares upon conversion to common stock |  |  |  |
Ending Balance |  |  | 7,134 | 6,729
Beginning Balance, Shares | 4,546,360 | 4,546,360 | 4,546,360 | 4,546,360
Issuance of shares, Shares |  |  |  |
Conversion to common stock, Shares | (4,546,360) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 4,546,360 | 4,546,360
Series C-1 Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 34,201 | 32,264 | 32,264 | 30,436
Issuance of shares |  |  |  |
Accretion of dividends | 1,272 |  | 1,937 | 1,828
Stock issuance costs |  |  |  |
Conversion to common stock | (35,473) |  |  |
Settlement of fractional shares upon conversion to common stock |  |  |  |
Ending Balance |  |  | 34,201 | 32,264
Beginning Balance, Shares | 15,934,528 | 15,934,528 | 15,934,528 | 15,934,528
Issuance of shares, Shares |  |  |  |
Conversion to common stock, Shares | (15,934,528) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 15,934,528 | 15,934,528
Series C-2 Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 44,512 | 41,987 | 41,987 | 39,605
Issuance of shares |  |  |  |
Accretion of dividends | 1,660 |  | 2,525 | 2,382
Stock issuance costs |  |  |  |
Conversion to common stock | (46,172) |  |  |
Settlement of fractional shares upon conversion to common stock |  |  |  |
Ending Balance |  |  | 44,512 | 41,987
Beginning Balance, Shares | 18,617,020 | 18,617,020 | 18,617,020 | 18,617,020
Issuance of shares, Shares |  |  |  |
Conversion to common stock, Shares | (18,617,020) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 18,617,020 | 18,617,020
Series C-3 Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 29,770 | 28,082 | 28,082 | 26,489
Issuance of shares |  |  |  |
Accretion of dividends | 1,103 |  | 1,688 | 1,593
Stock issuance costs |  |  |  |
Conversion to common stock | (30,873) |  |  |
Settlement of fractional shares upon conversion to common stock |  |  |  |
Ending Balance |  |  | 29,770 | 28,082
Beginning Balance, Shares | 13,297,872 | 13,297,872 | 13,297,872 | 13,297,872
Issuance of shares, Shares |  |  |  |
Conversion to common stock, Shares | (13,297,872) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 13,297,872 | 13,297,872
Series D Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 76,252 | 71,924 | 71,924 | 39,019
Issuance of shares |  |  |  | 28,942
Accretion of dividends | 2,827 |  | 4,328 | 3,971
Stock issuance costs |  |  |  | (8)
Conversion to common stock | (79,078) |  |  |
Settlement of fractional shares upon conversion to common stock | (1) |  |  |
Ending Balance |  |  | 76,252 | 71,924
Beginning Balance, Shares | 19,803,685 | 19,803,685 | 19,803,685 | 11,240,794
Issuance of shares, Shares |  |  |  | 8,562,891
Conversion to common stock, Shares | (19,803,685) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 19,803,685 | 19,803,685
Series E Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance | 211,403 | 117,954 | 117,954 |
Issuance of shares |  |  | 83,000 | 117,000
Accretion of dividends | 7,931 |  | 10,465 | 3,621
Stock issuance costs |  |  | (16) | (2,667)
Conversion to common stock | (219,332) |  |  |
Settlement of fractional shares upon conversion to common stock | (2) |  |  |
Ending Balance |  |  | 211,403 | 117,954
Beginning Balance, Shares | 38,095,239 | 22,285,716 | 22,285,716 |
Issuance of shares, Shares |  |  | 15,809,523 | 22,285,716
Conversion to common stock, Shares | (38,095,239) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  | 38,095,239 | 22,285,716
Series F Redeemable Convertible Preferred Stock [Member] |  |  |  |
Temporary Equity [Line Items] |  |  |  |
Beginning Balance |  |  |  |
Issuance of shares | 150,000 |  |  |
Accretion of dividends | 3,224 |  |  |
Stock issuance costs | (3,148) |  |  |
Conversion to common stock | (150,075) |  |  |
Settlement of fractional shares upon conversion to common stock | (1) |  |  |
Ending Balance | $ 0 |  |  |
Beginning Balance, Shares |  |  |  |
Issuance of shares, Shares | 19,047,619 |  |  |
Conversion to common stock, Shares | (19,047,619) |  |  |
Settlement of fractional shares upon conversion to common stock, Shares |  |  |  |
Ending Balance, Shares | 0 |  |  |

X
- Definition The value of the stock converted in a noncash (or part noncash) transaction. Noncash is defined as transactions during a period that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586 + Details
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- Definition Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. 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. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer. + References No definition available. + Details
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- Definition 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. + 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 + Details
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