Stockholder's Equity and Stock Based Compensation (Details) (USD $)	6 Months Ended		12 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Dec. 31, 2013
Stockholder's Equity and Stock Based Compensation
Common stock, shares authorized	1,000,000,000
Common stock, par value (in dollars per share)	$ 0.0001
Preferred stock, shares authorized	20,000,000
Preferred stock, par value (in dollars per share)	$ 0.0001
Common stock, shares issued	40,600,000
Common stock, shares outstanding	40,600,000
Stock options
Shares Available for Grant
Balance at the beginning of the period (in shares)	3,486,000
Additional shares authorized	1,962,000
Granted (in shares)	(870,000)
Repurchased (in shares)	68,000
RSUs granted, net of cancellations/forfeitures (in shares)	(1,068,000)
Cancelled/Forfeited (in shares)	250,000
Balance at the end of the period (in shares)	3,828,000		3,486,000
Number of Stock Options Outstanding
Balance at the beginning of the period (in shares)	6,343,000
Granted (in shares)	870,000
Exercised (in shares)	(989,000)
Cancelled/Forfeited (in shares)	(250,000)
Balance at the end of the period (in shares)	5,974,000		6,343,000
Exercisable at the end of the period (in shares)	4,935,000
Vested and expected to vest at the end of the period (in shares)	5,861,000
Weighted-Average Exercise Price
Balance at the beginning of the period (in dollars per share)	$ 5.33
Granted (in dollars per share)	$ 39.04
Exercised (in dollars per share)	$ 3.37
Repurchased (in dollars per share)	$ 25.86
Cancelled/Forfeited (in dollars per share)	$ 9.19
Balance at end of the period (in dollars per share)	$ 10.40		$ 5.33
Exercisable at the end of the period (in dollars per share)	$ 5.08
Vested and expected to vest at the end of the period (in dollars per share)	$ 10.52
Weighted-Average Remaining Contractual Life
Outstanding at the beginning of the period	7 years 11 months 12 days		7 years 11 months 23 days
Outstanding at the end of the period	7 years 11 months 12 days		7 years 11 months 23 days
Exercisable at the end of the period	7 years 7 months 28 days
Vested and expected to vest at the end of the period	7 years 11 months 16 days
Aggregate Intrinsic Value
Outstanding at the beginning of the period	$ 201,305,000
Outstanding at the end of the period	120,792,000		201,305,000
Exercisable at the end of the period	118,438,000
Vested and expected to vest at the end of the period	118,024,000
Closing stock price (in dollars per share)	$ 29.08
Additional information
Weighted average grant date fair value (in dollars per share)	$ 20.79	$ 4.44
Total intrinsic value of options exercised	33,190,000	4,855,000
Total estimated grant date fair value of options vested	$ 3,000,000
Vesting period	4 years
Percentage of awards which will vest after one year	25.00%