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- Definition

Temporary equity initial conversion price.

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- Definition

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

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Amount of dividends expected to be paid to holders of the underlying shares or contracted instruments over the term of the instruments life.

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Aggregate dividends declared during the period for each share of preferred stock outstanding.

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- Definition

Description of voting rights of nonredeemable preferred stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

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Number of shares issued during the period as a result of the conversion of convertible securities.

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

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The per share 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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Convertible Preferred Stock - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended		12 Months Ended
	Dec. 31, 2014	Jul. 22, 2014	Dec. 31, 2014	Dec. 31, 2013
Temporary Equity [Line Items]
Number of shares converted into common stock		510,777
Dividend declared per share			$ 0
Convertible preferred stock voting rights	Prior to conversion of all convertible preferred stock into common stock upon the Company’s IPO, each holder of shares of Series A, Series B, Series C, Series D, Series E, Series F, and Series G convertible preferred stock was entitled to voting rights equivalent to the number of shares of common stock into which their respective shares were convertible. So long as 14,599 shares of Series C convertible preferred stock remained outstanding, the holders of Series C convertible preferred stock were entitled to elect three members to the Company’s Board of Directors. So long as 14,599 shares of Series D and Series E convertible preferred stock remained outstanding, the holders of Series D and Series E convertible preferred stock were entitled to elect one member to the Board of Directors. So long as 14,599 shares of Series F and Series G convertible preferred stock remained outstanding, the holders of Series F and Series G convertible preferred stock were entitled to elect one member to the Company’s Board of Directors. The holders of Series A and B convertible preferred stock and the holders of common stock, voting together as a single class, were entitled to elect three members to the Board of Directors.
Convertible Preferred Stock [Member]
Temporary Equity [Line Items]
Number of shares converted into common stock		6,048,220
Series A Preferred Stock [Member]
Temporary Equity [Line Items]
Noncumulative dividends per share			$ 1.199
Number of shares issued for each share of convertible preferred stock				1
Initial conversion price per share				$ 17.12
Liquidation preferences per share	17.12		$ 17.12
Series B Preferred Stock [Member]
Temporary Equity [Line Items]
Noncumulative dividends per share			$ 3.720
Number of shares issued for each share of convertible preferred stock				0.18611
Initial conversion price per share				$ 13.43
Liquidation preferences per share	53.09		$ 53.09
Series C Preferred Stock [Member]
Temporary Equity [Line Items]
Noncumulative dividends per share			$ 1.199
Number of shares issued for each share of convertible preferred stock				1
Initial conversion price per share				$ 17.12
Liquidation preferences per share	17.12		$ 17.12
Minimum number of shares outstanding for voting rights	14,599
Series D Preferred Stock [Member]
Temporary Equity [Line Items]
Noncumulative dividends per share			$ 1.596
Number of shares issued for each share of convertible preferred stock				1
Initial conversion price per share				$ 21.78
Liquidation preferences per share	22.81		$ 22.81
Minimum number of shares outstanding for voting rights	14,599
Series E Preferred Stock [Member]
Temporary Equity [Line Items]
Noncumulative dividends per share			$ 2.219
Number of shares issued for each share of convertible preferred stock				1
Initial conversion price per share				$ 21.78
Liquidation preferences per share	31.72		$ 31.72
Minimum number of shares outstanding for voting rights	14,599
Series F Preferred Stock [Member]
Temporary Equity [Line Items]
Noncumulative dividends per share			$ 2.459
Number of shares issued for each share of convertible preferred stock				1
Initial conversion price per share				$ 21.78
Liquidation preferences per share	35.07		$ 35.07
Minimum number of shares outstanding for voting rights	14,599
Series G Preferred Stock [Member]
Temporary Equity [Line Items]
Noncumulative dividends per share			$ 1.528
Number of shares issued for each share of convertible preferred stock				1
Initial conversion price per share				$ 21.78
Liquidation preferences per share	21.78		$ 21.78
Minimum number of shares outstanding for voting rights	14,599
Convertible Subordinated Debt [Member]
Temporary Equity [Line Items]
Number of shares converted into common stock		510,777
Principal amount converted into common stock		5.0