Stock-Based Compensation Plans (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Stock-Based Compensation Plans
Stock-based compensation expense	$ 0	$ 4.2	$ 4.5	$ 9.3
Reduction in stock based compensation expense due to forfeitures	$ 2.9		$ 2.9
RSUs
Stock-Based Compensation Plans
Shares granted	1.6
Average grant date fair value (in dollars per share)	$ 0.86
Restricted stock awards
Stock-Based Compensation Plans
Shares granted	2.4
Average grant date fair value (in dollars per share)	$ 0.90
Options
Stock-Based Compensation Plans
Options granted (in share)	0.7
Average grant date fair value (in dollars per share)	$ 0.42
Weighted average exercise price (in dollars per share)	$ 0.87
Significant weighted average assumptions used to estimate fair value
Expected volatility (as a percent)	73.60%
Expected term	3 years 3 months 18 days
Risk-free interest rate (as a percent)	0.50%
Expiration term of awards	6 years