Stockholders' Equity (Tables)

9 Months Ended

Sep. 30, 2012

Stockholders' Equity Note [Abstract]

Schedule of change in the number of shares of Class A common stock

The following table sets forth the change in the number of shares of our Class A common stock outstanding during the nine months ended September 30, 2012 and during the fiscal year ended December 31, 2011:

	Nine Months Ended		Twelve Months Ended
	September 30, 2012		December 31, 2011
Shares outstanding as of beginning of period	92,433		91,725
Shares issued as part of equity-based compensation plans and the Employee    Stock Purchase Plan (“ESPP”), net of restricted stock units ("RSUs")	696		708
Shares repurchased into treasury stock	(6,422	)	—
Shares outstanding as of end of period	86,707		92,433

During the nine months ended September 30, 2012, the Company repurchased 6,422 shares under its previously announced repurchase program for $47,401. From October 1, 2012 to November 2, 2012, the Company repurchased an additional 1,670 shares for $13,266.