Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Class of Stock [Line Items]
Convertible preferred stock, shares issued		9,796,342us-gaap_TemporaryEquitySharesIssued
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	290,000,000us-gaap_CommonStockSharesAuthorized	163,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares issued	17,907,135us-gaap_CommonStockSharesIssued	392,844us-gaap_CommonStockSharesIssued
Common stock, shares outstanding	17,907,135us-gaap_CommonStockSharesOutstanding	392,844us-gaap_CommonStockSharesOutstanding
Preferred stock, par value	$ 0.001
Preferred stock, shares outstanding	0us-gaap_PreferredStockSharesOutstanding
Preferred stock, shares authorized	10,000,000us-gaap_PreferredStockSharesAuthorized
Preferred stock, shares issued	0us-gaap_PreferredStockSharesIssued
Convertible preferred stock
Class of Stock [Line Items]
Convertible preferred stock, par value	$ 0.001	$ 0.001
Convertible preferred stock, shares authorized	0	132,202,910
Convertible preferred stock, shares issued	0	9,796,342
Convertible preferred stock, shares outstanding	0	9,796,342
Liquidation value		$ 132,809

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Face amount or stated value per share of common stock.

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