Pension and Other Post Retirement Benefits (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) $ / hour	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Defined Benefit Plan Disclosure [Line Items]
IAM Level of Contribution per hour until June 2010 | $ / hour	1.75
Amounts recognized in balance sheet
Noncurrent assets	$ 326.7	$ 347.1
Noncurrent liabilities	34.6	40.8
Domestic Plan [Member]
Change in fair value of plan assets:
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant	0.0	0.0
Other Benefits [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	0.0	0.0
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	47.2	51.5
Service cost	1.1	1.2
Interest cost	1.0	1.2
Actuarial (gains) losses	2.4	(1.0)
Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits	0.0	0.0
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment	0.0	0.0
Defined Benefit Plan, Benefit Obligation, Benefits Paid	7.6	8.8
Projected benefit obligation at the end of the period	40.3	47.2	$ 51.5
Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant	$ 1.0	$ 1.1
Total recognized in net periodic benefit cost and OCI
Discount rate	3.74%	3.03%
Medical Assumptions:
Trend assumed for the year	6.24%	6.59%
Ultimate trend rate	4.50%	4.50%
Year that ultimate trend rate is reached	2038	2038
Change in fair value of plan assets:
Beginning balance	$ 0.0	$ 0.0
Company contributions	6.6	7.7
Defined Benefit Plan, Plan Assets, Contributions by Plan Participant	1.0	1.1
Defined Benefit Plan, Plan Assets, Administration Expense	0.0	0.0
Defined Benefit Plan, Plan Assets, Benefits Paid	7.6	8.8
Ending balance	0.0	0.0	0.0
Reconciliation of funded status to net amounts recognized:
Funded status (deficit)	(40.3)	(47.2)
Net amounts recognized	(40.3)	(47.2)
Amounts recognized in balance sheet
Noncurrent assets	0.0	0.0
Current liabilities	6.9	7.7
Noncurrent liabilities	(33.4)	(39.5)
Net amounts recognized	(40.3)	(47.2)
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	27.5	28.3
Accumulated other comprehensive income (AOCI)	27.5	28.3
Cumulative employer contributions in excess of net periodic benefit cost	(67.8)	(75.5)
Net amount recognized in the balance sheet	(40.3)	(47.2)
Information for pension plans with benefit obligations in excess of plan assets:
Projected benefit obligation	40.3	47.2
Accumulated benefit obligation	0.0	0.0
Pension Plan [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	(77.1)	174.5
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	1,084.4	1,036.0
Service cost	0.0	0.0
Interest cost	34.7	35.6
Actuarial (gains) losses	91.7	(80.0)
Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits	0.0	0.0
Defined Benefit Plan, Benefit Obligation, Increase (Decrease) for Plan Amendment	0.0	0.0
Defined Benefit Plan, Benefit Obligation, Benefits Paid	30.4	67.2
Projected benefit obligation at the end of the period	997.0	1,084.4	1,036.0
Defined Benefit Plan, Benefit Obligation, Contributions by Plan Participant	$ 0.0	$ 0.0
Total recognized in net periodic benefit cost and OCI
Discount rate	4.21%	3.59%
Change in fair value of plan assets:
Beginning balance	$ 1,410.3	$ 1,302.9
Company contributions	0.1	0.1
Defined Benefit Plan, Plan Assets, Administration Expense	0.0	0.0
Defined Benefit Plan, Plan Assets, Benefits Paid	30.5	67.2
Ending balance	1,302.8	1,410.3	1,302.9
Reconciliation of funded status to net amounts recognized:
Funded status (deficit)	305.8	325.9
Net amounts recognized	305.8	325.9
Amounts recognized in balance sheet
Noncurrent assets	307.0	327.2
Current liabilities	0.0	0.0
Noncurrent liabilities	(1.2)	(1.3)
Net amounts recognized	305.8	325.9
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	(141.9)	(89.6)
Accumulated other comprehensive income (AOCI)	(141.9)	(89.6)
Cumulative employer contributions in excess of net periodic benefit cost	447.7	415.5
Net amount recognized in the balance sheet	305.8	325.9
Information for pension plans with benefit obligations in excess of plan assets:
Projected benefit obligation	1.2	1.3
Accumulated benefit obligation	1.2	1.3
Pension Plan [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Actual Return (Loss)	(3.0)	8.7
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Curtailment	(7.5)	(12.5)
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	76.9	82.1
Service cost	1.3	1.3
Interest cost	1.7	2.0
Actuarial (gains) losses	6.9	1.1
Defined Benefit Plan, Benefit Obligation, Benefits Paid	0.6	0.8
Expense paid	(1.3)	(1.3)
Exchange rate changes	(3.7)	7.2
Projected benefit obligation at the end of the period	$ 59.9	$ 76.9	82.1
Total recognized in net periodic benefit cost and OCI
Discount rate	3.00%	2.60%
Salary increases	3.40%	3.35%
Change in fair value of plan assets:
Beginning balance	$ 96.8	$ 96.2
Company contributions	1.7	0.0
Expense paid	(1.3)	(1.3)
Defined Benefit Plan, Plan Assets, Administration Expense	(1.3)	(1.3)
Exchange rate changes	(4.9)	8.7
Defined Benefit Plan, Plan Assets, Payment for Settlement	(9.1)	(14.7)
Defined Benefit Plan, Plan Assets, Benefits Paid	0.6	0.8
Ending balance	79.6	96.8	96.2
Reconciliation of funded status to net amounts recognized:
Funded status (deficit)	19.7	19.9
Net amounts recognized	19.7	19.9
Amounts recognized in balance sheet
Noncurrent assets	19.7	19.9
Net amounts recognized	19.7	19.9
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	3.1	4.3
Accumulated other comprehensive income (AOCI)	3.1	4.3
Prepaid pension cost	16.6	15.6
Net amount recognized in the balance sheet	19.7	19.9
Annual Expense [Member] | Other Benefits [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)	(2.3)	(2.2)	0.0
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax	(0.2)	(3.5)	16.9
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	1.1	1.2	1.8
Interest cost	1.1	1.2	2.1
Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits	$ 0.0	$ 0.0	$ (3.1)
Total recognized in net periodic benefit cost and OCI
Discount rate	3.03%	3.21%	3.43%
Medical Assumptions:
Trend assumed for the year	6.59%	6.93%	7.27%
Ultimate trend rate	4.50%	4.50%	4.50%
Year that ultimate trend rate is reached	2038	2038	2038
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	$ 0.8	$ 4.2	$ (23.0)
Accumulated other comprehensive income (AOCI)	0.8	4.2	(23.0)
Annual Expense [Member] | Pension Plan [Member] | Domestic Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)	0.0	0.0	5.7
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax	20.1	58.9	34.7
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	0.0	0.0	0.0
Interest cost	34.7	35.7	42.7
Defined Benefit Plan, Benefit Obligation, Special and Contractual Termination Benefits	$ 0.0	$ 0.0	$ (23.6)
Total recognized in net periodic benefit cost and OCI
Discount rate	3.59%	4.15%	4.38%
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	$ 52.3	$ (24.8)	$ (31.8)
Accumulated other comprehensive income (AOCI)	52.3	(24.8)	(31.8)
Annual Expense [Member] | Pension Plan [Member] | Foreign Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Gain (Loss) Due to Settlement	(0.4)	(0.3)	0.0
Defined Benefit Plan, Accumulated Other Comprehensive Income (Loss), Gain (Loss), before Tax	(0.7)	6.6	4.3
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	1.3	1.3	1.0
Interest cost	$ 1.7	$ 2.0	$ 2.9
Total recognized in net periodic benefit cost and OCI
Discount rate	2.60%	2.70%	4.00%
Salary increases	3.35%	3.20%	3.10%
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	$ (0.5)	$ (6.7)	$ (4.6)
Accumulated other comprehensive income (AOCI)	$ (0.5)	$ (6.7)	$ (4.6)