|
Income Taxes (Details) (USD $)
In Millions, unless otherwise specified |
3 Months Ended | |
|---|---|---|
|
Mar. 31, 2011
|
Mar. 31, 2010
|
|
| Income Taxes [Abstract] | ||
| Amount of income tax expense, inclusive of interest and penalties, related to a prior year tax examination | $ 4.7 | |
| Recognition of a liability for unrecognized tax benefit from prior year | $ 3.2 | |
| Consolidated effective income tax rate including tax expense attributable to prior period | 20.60% | |
| Consolidated effective income tax rate excluding tax expense attributable to prior periods | 14.90% | 17.80% |