Stockholders' Equity (Tables)

12 Months Ended

Dec. 31, 2012

Equity [Abstract]

Schedule of Convertible Preferred Stock Immediately Prior to Conversion

Upon the closing of our IPO, all shares of our then-outstanding convertible preferred stock, as shown on the table below, automatically converted into an aggregate of 545,401,443 shares of our Class B common stock.

The following table summarizes the convertible preferred stock o

Stock Option and RSU Award Activity under Stock Plans

The following table summarizes the stock option and RSU award activities under the Stock Plans for the year ended December 31, 2012:

			Shares Subject to Options Outstanding							Outstanding RSUs
	Shares Available for Grant(1)		Number of Shares		Weighted Average Exercise Price		Weighted- Average Remaining Contractual Term	Aggregate Intrinsic Value(2)		Outstanding RSUs(3)		Weighted Average Grant Date Fair Value
	(in thousands)		(in thousands)				(in years)	(in millions)		(in thousands)
Balance as of December 31, 2011	52,318		258,539		$	0.47	4.38	$	7,360	378,772		$	6.83
Stock options exercised	—		(135,505	)	0.12					—
Stock options forfeited/cancelled	213		(213	)	1.41					—
RSUs granted	(41,252	)	—							41,252		32.60
RSUs settled	—		—							(278,846	)	3.02
Shares withheld related to net share settlement of RSUs	122,757		—							—
RSUs forfeited and cancelled	12,955		—							(12,955	)	20.00
2012 Equity Incentive Plan shares authorized	25,000		—							—
Balance as of December 31, 2012	171,991		122,821		$	0.85	3.79	$	3,166	128,223		$	22.08
Stock options vested and expected to vest as of December 31, 2012			122,791		$	0.85	3.79	$	3,166
Stock options exercisable as of December 31, 2012			113,688		$	0.34	3.53	$	2,989

(1) After excluding 195 thousand restricted stock awards included in the table above, 171,796 thousand shares are available for grant under the Stock Plans as of December 31, 2012.

(2) The aggregate intrinsic value is calculated as the difference between the exercise price of the underlying stock option awards and the assessed fair value of our common stock as of December 31, 2011 and the closing market price of our common stock as of December 31, 2012.

(3) During the year ended December 31, 201269,196 thousand RSUs were vested and the total grant date fair value of these RSUs vested is $9.14. As of December 31, 2012 and 2011, we have 113,044 thousand and 153,943 thousand of unvested RSUs.

Fair Value of Employee Options Granted, Weighted-Average Assumptions

The fair values of employee options granted during 2010 have been estimated as of the date of grant using the following weighted-average assumptions.

	December 31, 2010
Expected term from grant date (in years)	7.15
Risk-free interest rate	1.69%
Expected volatility	0.46
Dividend yield	—

Outstanding and Exercisable Options Under Stock Plans

The following table summarizes additional information regarding outstanding and exercisable options under the Stock Plans at

December 31, 2012:

	Options Outstanding				Options Exercisable
Exercise Price (Range)	Number of Shares	Weighted- Average Remaining Life	Weighted- Average Exercise Price		Number of Shares	Weighted- Average Exercise Price
	(in thousands)	(in years)			(in thousands)
$0.00 - 0.04	5,381	2.65	$	0.04	5,381	$	0.04
0.06	63,379	2.86	0.06		63,379	0.06
0.10 - 0.18	18,096	3.66	0.15		18,096	0.15
0.29 - 0.33	14,701	4.40	0.31		14,701	0.31
1.78	4,693	5.59	1.78		3,701	1.78
1.85	4,865	6.04	1.85		3,938	1.85
2.95	2,506	6.64	2.95		1,567	2.95
3.23	4,500	6.82	3.23		2,925	3.23
10.39	3,500	7.56	10.39		—	—
15.00	1,200	7.81	15.00		—	—
	122,821	3.79	$	0.85	113,688	$	0.34