Share-Based Compensation Plans Schedule of stock option valuation assumptions used (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]
Dividend yield	0.73%	0.00%	0.00%
Expected volatility	52.60%	56.10%	45.70%
Risk-free interest rate	0.50%	1.30%	2.60%
Expected life of options in years	3 years 7 months 7 days	3 years 7 months 7 days	6 years 8 months 13 days
Weighted average grant date fair value (in dollars per share)	$ 10.18	$ 12.23	$ 12.18