Earnings Per Share Table (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Earnings Per Share [Abstract]
Net income, basic	$ 10.5	$ 12.0	$ 24.2	$ 21.0
Weighted-average shares outstanding, basic EPS	11.5	11.4	11.4	11.4
Net income per common share, basic EPS	$ 0.92	$ 1.05	$ 2.12	$ 1.84
Effect of dilutive common share equivalents: [Abstract]
Incremental common shares attributable to share-based payment arrangements, restricted stock units	0.1	0.1	0.1	0.1
Net income per common share, restricted stock units	$ (0.01)	$ 0.00	$ (0.02)	$ (0.01)
Incremental common shares attributable to share-based payment arrangements, stock options	0.1	0.1	0.1	0.1
Net income per common share, stock options	$ (0.01)	$ (0.01)	$ (0.02)	$ (0.02)
Incremental common shares attributable to warrants	0	0.1	0	0.2
Net income per common share, warrants	$ 0.00	$ (0.01)	$ 0.00	$ (0.03)
Net income, diluted	$ 10.5	$ 12.0	$ 24.2	$ 21.0
Weighted-average shares outstanding, diluted EPS	11.7	11.7	11.6	11.8
Net income per common share, diluted EPS	$ 0.90	$ 1.03	$ 2.08	$ 1.78