Stockholders' Equity (Deficit) (Details 2) (Class A common stock, USD $) In Billions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Class A common stock
Stockholders Equity (Deficit)
Maximum amount authorized for common stock repurchase under common stock repurchase program	$ 1.0
Amount authorized for common stock repurchase under common stock repurchase program	$ 1.0
Information regarding repurchase of Class A common stock
Total number of shares repurchased	0	0	0