Stockholders' Equity (Narrative) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	1 Months Ended	3 Months Ended	6 Months Ended			1 Months Ended	3 Months Ended	1 Months Ended	3 Months Ended		6 Months Ended
	Apr. 30, 2013	Jun. 30, 2013	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 Series A Common Stock [Member]	Apr. 30, 2013 Quarterly [Member]	Mar. 31, 2013 Quarterly [Member]	Apr. 30, 2013 Annual [Member]	Mar. 31, 2013 Annual [Member]	Jun. 30, 2013 Equity Method Investments' Derivative [Member]	Jun. 30, 2013 Equity Method Investments' Derivative [Member]
Class of Stock [Line Items]
Derivative, Gain (Loss) on Derivative, Net										$ (1)	$ (1)
Other Comprehensive Income (Loss), Net of Tax Portion Attributable To Equity Method Investee		$ (1)	$ (1)	$ (2)
Common Stock, Dividends, Per Share, Declared						$ 0.09	$ 0.075	$ 0.36	$ 0.30
Common stock, par value					$ 0.0001
Common Stock, Dividends, Rate Increase, Percent	20.00%