Accumulated Comprehensive Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle	$ (4.4)		$ 15.9
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, Tax	(3.1)	$ (4.5)	(0.3)
Accumulated comprehensive loss, net of tax, beginning of period	(146.4)	(122.1)	(137.2)	$ (146.1)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(12.4)	10.2	2.9
Other Comprehensive Income (Loss) before Reclassifications, Tax	1.3	1.4	(2.2)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(13.7)	8.8	5.1
Reclassification from accumulated other comprehensive income, current period, before tax	8.1	9.7	6.0
Reclassification from AOCI, Current Period, Tax	(2.0)	(3.4)	(2.2)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	6.1	6.3	3.8
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(7.6)	15.1	8.9
Accumulated comprehensive loss, net of tax, end of period	(146.4)	(122.1)	(137.2)	(146.1)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated comprehensive loss, net of tax, beginning of period	(57.0)	(39.7)	(46.3)	(55.1)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	(17.3)	6.6	8.8
Other Comprehensive Income (Loss) before Reclassifications, Tax	0.0	0.0	0.0
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	(17.3)	6.6	8.8
Reclassification from accumulated other comprehensive income, current period, before tax	0.0	0.0	0.0
Reclassification from AOCI, Current Period, Tax	0.0	0.0	0.0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.0	0.0	0.0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(17.3)	6.6	8.8
Accumulated comprehensive loss, net of tax, end of period	(57.0)	(39.7)	(46.3)	(55.1)
Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle	(17.4)
Accumulated comprehensive loss, net of tax, beginning of period	(88.2)	(79.5)	(87.7)	(87.8)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	4.1	3.2	(5.3)
Other Comprehensive Income (Loss) before Reclassifications, Tax	1.1	1.1	(1.9)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	3.0	2.1	(3.4)
Reclassification from accumulated other comprehensive income, current period, before tax	7.6	9.3	5.5
Reclassification from AOCI, Current Period, Tax	(1.9)	(3.2)	(2.0)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	5.7	6.1	3.5
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	8.7	8.2	0.1
Accumulated comprehensive loss, net of tax, end of period	(88.2)	(79.5)	(87.7)	(87.8)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated comprehensive loss, net of tax, beginning of period	(4.5)	(4.9)	(5.2)	(5.5)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	0.0	0.0	0.0
Other Comprehensive Income (Loss) before Reclassifications, Tax	0.0	0.0	0.0
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0.0	0.0	0.0
Reclassification from accumulated other comprehensive income, current period, before tax	0.5	0.5	0.5
Reclassification from AOCI, Current Period, Tax	(0.1)	(0.2)	(0.2)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.4	0.3	0.3
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0.4	0.3	0.3
Accumulated comprehensive loss, net of tax, end of period	(4.5)	(4.9)	(5.2)	(5.5)
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle	0.7
Accumulated comprehensive loss, net of tax, beginning of period	4.3	3.5	2.7	3.3
Other Comprehensive Income (Loss), before Reclassifications, before Tax	0.1	1.3	(1.0)
Other Comprehensive Income (Loss) before Reclassifications, Tax	0.0	0.5	(0.4)
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0.1	0.8	(0.6)
Reclassification from accumulated other comprehensive income, current period, before tax	0.0	0.0	0.0
Reclassification from AOCI, Current Period, Tax	0.0	0.0	0.0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.0	0.0	0.0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0.1	0.8	(0.6)
Accumulated comprehensive loss, net of tax, end of period	4.3	3.5	2.7	3.3
Accumulated Other Post Retirement Benefits Adjustment, Net [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated comprehensive loss, net of tax, beginning of period	(1.0)	(1.5)	(0.7)	(1.0)
Other Comprehensive Income (Loss), before Reclassifications, before Tax	0.7	(0.9)	0.4
Other Comprehensive Income (Loss) before Reclassifications, Tax	0.2	(0.2)	0.1
Other Comprehensive Income (Loss), before Reclassifications, Net of Tax	0.5	(0.7)	0.3
Reclassification from accumulated other comprehensive income, current period, before tax	0.0	(0.1)	0.0
Reclassification from AOCI, Current Period, Tax	0.0	0.0	0.0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0.0	(0.1)	0.0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	0.5	(0.8)	0.3
Accumulated comprehensive loss, net of tax, end of period	(1.0)	$ (1.5)	$ (0.7)	$ (1.0)
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income Tax Effects Allocated Directly to Equity, Cumulative Effect of Change in Accounting Principle	$ (16.7)