CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (USD $) In Millions, unless otherwise specified	Total	Additional Paid-In Capital [Member]	Accumulated Deficit [Member]	Treasury Stock [Member]	Accumulated other comprehensive loss [Member]	Class A Common Stock [Member] Common Stock [Member]	Class B Common Stock [Member] Common Stock [Member]
Balance at Dec. 31, 2011	$ 409	$ 1,556	$ (1,082)	$ 0	$ (65)	$ 0	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(304)	0	(304)	0	0	0	0
Net impact of interest rate derivative instruments, net of tax	(10)	0	0	0	(10)	0	0
Stock compensation expense, net	50	50	0	0	0	0	0
Exercise of options	15	15	0	0	0	0	0
Purchase of treasury stock	(11)	0	0	(11)	0	0	0
Retirement of treasury stock	0	(5)	(6)	11	0	0	0
Balance at Dec. 31, 2012	149	1,616	(1,392)	0	(75)	0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(169)	0	(169)	0	0	0	0
Net impact of interest rate derivative instruments, net of tax	34	0	0	0	34	0	0
Stock compensation expense, net	48	48	0	0	0	0	0
Exercise of options and warrants	104	104	0	0	0	0	0
Purchase of treasury stock	(15)	0	0	(15)	0	0	0
Retirement of treasury stock	0	(8)	(7)	15	0	0	0
Balance at Dec. 31, 2013	151	1,760	(1,568)	0	(41)	0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(183)	0	(183)	0	0	0	0
Net impact of interest rate derivative instruments, net of tax	19	0	0	0	19	0	0
Stock compensation expense, net	55	55	0	0	0	0	0
Exercise of options and warrants	123	123	0	0	0	0	0
Purchase of treasury stock	(19)	0	0	(19)	0	0	0
Retirement of treasury stock	0	(8)	(11)	19	0	0	0
Balance at Dec. 31, 2014	$ 146	$ 1,930	$ (1,762)	$ 0	$ (22)	$ 0	$ 0