Income Taxes (Deferred Tax Valuation Allowance) (Details) - Valuation Allowance of Deferred Tax Assets - USD ($) $ in Millions |
12 Months Ended | ||
---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
Movement in Deferred Tax Valuation Allowances [Roll Forward] | |||
Balance at beginning of year | $ 72.4 | $ 62.3 | $ 63.7 |
Additions charged to provision for income taxes | 0.9 | 12.9 | 0.3 |
Deferred tax assets realized or written-off | (5.9) | (2.8) | (1.4) |
Other, net | 0.0 | 0.0 | (0.3) |
Balance at end of year | 73.5 | 72.4 | 62.3 |
Expirations Of State Net Operating Losses [Member] | |||
Movement in Deferred Tax Valuation Allowances [Roll Forward] | |||
Current year acquisitions | $ 6.1 | $ 0.0 | $ 0.0 |