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Stock-Based Incentive Plans Options Value Assumptions (Details)	12 Months Ended
	Dec. 31, 2011 year	Dec. 31, 2010 year	Dec. 31, 2009 year
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Risk free interest rate	1.80%	2.20%	2.00%
Weighted average historical volatility	79.10%	80.40%	72.30%
Dividend yield		0.00%	0.00%
Expected years until exercise	4.6	4.8	5.0
Forfeitures	11.00%	11.00%	11.00%

The period of time an equity-based award is expected to be outstanding. An equity-based award's expected term is generally determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior.

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