Retirement Benefits Narrative (Details)	3 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($) benefit_plan	Dec. 31, 2016 USD ($) benefit_plan	Dec. 31, 2015 USD ($) benefit_plan	Dec. 31, 2014 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Accumulated benefit obligation	$ 876,200,000	$ 876,200,000	$ 842,100,000
Number of defined contribution pension plans (benefit plan) | benefit_plan	6	6
Defined contribution pension plans, total costs		$ 15,600,000	$ 13,300,000	$ 12,900,000
Number of multiemployer defined benefit pension plans (benefit_plan) | benefit_plan	2	2	2
Multiemployer plan total employer contributions		$ 500,000	$ 800,000	0.8
Pre-tax restructuring costs		35,000,000	23,600,000	5,100,000
Expected cost remaining	$ 12,200,000	12,200,000
Employer stock included in plan assets	$ 40,000,000	$ 40,000,000	$ 34,700,000
Employer stock as percentage of plan assets	6.60%	6.60%	5.30%
US Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Curtailment gain		$ 34,100,000
Amortization of prior service cost (credit)		200,000
Projected benefit obligation		$ 40,000,000
Voluntary lump sum program payment			$ 27,700,000
Defined benefit obligation per plan, as a percent of total benefit obligation		87.00%
Discount rate	4.30%	4.30%	4.80%
Effect on defined benefit obligation, due to change in mortality table utilized				40,000,000
Employer contributions		$ 16,000,000
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Amortization of prior service cost (credit)		100,000	$ 200,000	200,000
Benefit obligation	$ 917,400,000	$ 917,400,000	$ 912,300,000	$ 976,300,000
Number of multiemployer defined benefit pension plans (benefit_plan) | benefit_plan	2	2
Multiemployer plan, number of plans under 65% funded (benefit_plan) | benefit_plan	1	1
Defined benefit plan, funded percentage	65.00%	65.00%
Discount rate	4.12%	4.12%	4.71%	4.23%
Employer contributions		$ 24,300,000	$ 27,900,000
Foreign Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Estimated future employer contributions in next fiscal year		$ 1,700,000
Foreign Pension Plan | Canada
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.85%	3.85%	3.90%
Foreign Pension Plan | United Kingdom
Defined Benefit Plan Disclosure [Line Items]
Discount rate	2.70%	2.70%	4.00%
Withdrawal from Multiemployer Defined Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Pre-tax restructuring costs	$ 12,500,000
Expected cost remaining	$ 28,000,000	$ 28,000,000