Pension and Other Post Retirement Benefits (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) $ / hour	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Defined Benefit Plan Disclosure [Line Items]
IAM Level of Contribution per hour until June 2010 | $ / hour	1.75
Change in fair value of plan assets:
Employee contributions	$ 0.0	$ 0.0
Amounts recognized in balance sheet
Noncurrent assets	246.9	203.4
Noncurrent liabilities	(67.7)	(73.0)
U.S. qualified pension plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	1,124.4	949.4
Service cost	0.0	0.0
Interest cost	44.4	45.9
Actuarial (gains) and losses	113.5	173.2
Defined Benefit Plan, Special Termination Benefits	0.0	1.6
Benefits paid	(44.2)	(45.7)
Projected benefit obligation at the end of the period	$ 1,011.1	$ 1,124.4	$ 949.4
Total recognized in net periodic benefit cost and OCI
Discount rate	4.38%	3.99%
Change in fair value of plan assets:
Employee contributions	$ 0.0	$ 0.0
Reconciliation of funded status to net amounts recognized:
Funded status (deficit)	232.1	186.5
Net amounts recognized	232.1	186.5
Amounts recognized in balance sheet
Noncurrent assets	233.3	187.8
Current liabilities	0.1	0.1
Noncurrent liabilities	1.1	(1.2)
Net amounts recognized	232.1	186.5
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	(146.2)	(161.8)
Accumulated other comprehensive income (AOCI)	(146.2)	(161.8)
Cumulative employer contributions in excess of net periodic benefit cost	378.3	348.3
Net amount recognized in the balance sheet	232.1	186.5
Information for pension plans with benefit obligations in excess of plan assets:
Projected benefit obligation/APBO	1.2	1.3
Accumulated benefit obligation	1.2	1.3
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	(146.2)	(161.8)
U.S. qualified pension plan [Member] | Fair Value [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefits paid	(44.2)	(45.7)
Change in fair value of plan assets:
Beginning balance	1,310.9	1,179.3
Actual return (loss) on assets	(23.6)	177.3
Company contributions	0.1	0.0
Expenses paid	0.0	0.0
Ending balance	1,243.2	1,310.9	1,179.3
Other Postretirement Benefit Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	77.5	71.6
Service cost	2.2	2.3
Interest cost	2.2	2.7
Actuarial (gains) and losses	6.1	0.8
Defined Benefit Plan, Special Termination Benefits	0.0	1.7
Benefits paid	(3.0)	(1.8)
Projected benefit obligation at the end of the period	$ 73.3	$ 77.5	71.6
Total recognized in net periodic benefit cost and OCI
Discount rate	3.43%	3.14%
Medical Assumptions:
Trend assumed for the year	7.27%	7.62%
Ultimate trend rate	4.50%	4.50%
Year that ultimate trend rate is reached	2038	2030
Change in fair value of plan assets:
Employee contributions	$ 0.5	$ 0.2
Reconciliation of funded status to net amounts recognized:
Funded status (deficit)	(73.3)	(77.5)
Net amounts recognized	(73.3)	(77.5)
Amounts recognized in balance sheet
Noncurrent assets	0.0	0.0
Current liabilities	6.8	(5.8)
Noncurrent liabilities	66.5	(71.7)
Net amounts recognized	(73.3)	(77.5)
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	9.5	3.4
Accumulated other comprehensive income (AOCI)	9.5	3.4
Cumulative employer contributions in excess of net periodic benefit cost	(82.8)	(80.9)
Net amount recognized in the balance sheet	(73.3)	(77.5)
Information for pension plans with benefit obligations in excess of plan assets:
Projected benefit obligation/APBO	73.3	77.5
Accumulated benefit obligation	0.0	0.0
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	9.5	3.4
Other Postretirement Benefit Plan [Member] | Fair Value [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefits paid	(3.0)	(1.8)
Change in fair value of plan assets:
Beginning balance	0.0	0.0
Actual return (loss) on assets	0.0	0.0
Company contributions	2.5	1.5
Employee contributions	0.5	0.3
Expenses paid	0.0	0.0
Ending balance	0.0	0.0	0.0
U.K. pension plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Beginning balance	89.1	78.3
Service cost	1.2	0.7
Interest cost	3.3	3.7
Actuarial (gains) and losses	3.2	13.6
Benefits paid	(1.6)	(1.0)
Expense paid	(1.2)	(0.7)
Exchange rate changes	(4.8)	(5.5)
Projected benefit obligation at the end of the period	$ 82.8	$ 89.1	78.3
Total recognized in net periodic benefit cost and OCI
Discount rate	4.00%	3.80%
Salary increases	3.10%	3.15%
Change in fair value of plan assets:
Expense paid	$ (1.2)	$ (0.7)
Reconciliation of funded status to net amounts recognized:
Funded status (deficit)	13.6	15.6
Net amounts recognized	13.6	15.6
Amounts recognized in balance sheet
Noncurrent assets	13.6	15.6
Net amounts recognized	13.6	15.6
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	(3.9)	(2.3)
Accumulated other comprehensive income (AOCI)	(3.9)	(2.3)
Prepaid (unfunded accrued) pension cost	17.5	17.9
Net amount recognized in the balance sheet	13.6	15.6
Information for pension plans with benefit obligations in excess of plan assets:
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments			(13.1)
U.K. pension plan [Member] | Fair Value [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefits paid	(1.6)	(1.0)
Expense paid	(1.1)	(0.7)
Change in fair value of plan assets:
Beginning balance	104.7	99.7
Actual return (loss) on assets	(0.1)	12.5
Company contributions	0.1	0.7
Expense paid	(1.1)	(0.7)
Exchange rate changes	(5.6)	(6.5)
Ending balance	96.4	104.7	99.7
Annual Expense [Member] | U.S. qualified pension plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gains (Losses)	3.7	0.0	11.8
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	0.0	0.0	0.0
Interest cost	44.4	45.9	42.9
Defined Benefit Plan, Special Termination Benefits	$ 0.0	$ (1.7)	$ 4.1
Total recognized in net periodic benefit cost and OCI
Discount rate	3.99%	4.89%	4.01%
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	$ (15.5)	$ 72.0	$ (131.8)
Accumulated other comprehensive income (AOCI)	(15.5)	72.0	(131.8)
Information for pension plans with benefit obligations in excess of plan assets:
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	(45.5)	(43.5)	161.2
Annual Expense [Member] | Other Postretirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gains (Losses)	0.0	0.0	0.0
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	2.2	2.3	2.7
Interest cost	2.2	2.7	2.1
Defined Benefit Plan, Special Termination Benefits	$ 0.0	$ (1.7)	$ 0.0
Total recognized in net periodic benefit cost and OCI
Discount rate	3.14%	3.89%	2.94%
Medical Assumptions:
Trend assumed for the year	7.62%	8.50%	8.50%
Ultimate trend rate	4.50%	4.50%	4.50%
Year that ultimate trend rate is reached	2030	2030	2030
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	$ (6.1)	$ 0.8	$ (8.6)
Accumulated other comprehensive income (AOCI)	(6.1)	0.8	(8.6)
Information for pension plans with benefit obligations in excess of plan assets:
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	(1.7)	(7.5)	3.8
Annual Expense [Member] | U.K. pension plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gains (Losses)	0.0	0.0	(0.1)
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Service cost	1.2	0.7	7.2
Interest cost	$ 3.3	$ 3.6	$ 3.2
Total recognized in net periodic benefit cost and OCI
Discount rate	3.80%	4.75%	4.70%
Salary increases	3.05%	3.25%	3.10%
Amounts not yet reflected in net periodic benefit cost and included in AOCI:
Accumulated gain (loss)	$ 1.5	$ 6.8	$ 4.5
Accumulated other comprehensive income (AOCI)	1.5	6.8	4.5
Information for pension plans with benefit obligations in excess of plan assets:
Pension and Other Postretirement Benefit Plans, Accumulated Other Comprehensive Income (Loss), Net Gains (Losses), before Tax	1.1	(5.4)	2.9
Defined Benefit Plan, Recognized Net Gain (Loss) Due to Curtailments	$ 0.0	$ 0.0	$ (13.1)