CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Allowance for doubtful accounts	$ 400	$ 332
Redeemable convertible preferred stock, par value	$ 0.00001	$ 0.00001
Redeemable convertible preferred stock, shares authorized	0	50,437,000
Redeemable convertible preferred stock, shares issued	0	41,529,721
Redeemable convertible preferred stock, shares outstanding	0	41,529,721
Redeemable convertible preferred stock, liquidation preference	$ 0	$ 282,990
Preferred stock, par value	$ 0.00001	$ 0.00001
Preferred stock, shares authorized	10,000,000	0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.00001	$ 0.00001
Common stock, shares authorized	250,000,000	96,000,000
Common stock, shares issued	82,419,992	25,934,206
Common stock, shares outstanding	77,575,086	21,089,300