Retirement Benefit Plans - Asset Allocations (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year, Under Contractual Obligation	$ 4.0
Domestic Plan [Member] | Pension Plan [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	100.00%	100.00%
Domestic Plan [Member] | Pension Plan [Member] | Real estate and other [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	11.00%	11.00%
Domestic Plan [Member] | Pension Plan [Member] | Fixed income securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	56.00%	53.00%
Domestic Plan [Member] | Pension Plan [Member] | Equity securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	33.00%	36.00%
Foreign Plan [Member] | Pension Plan [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	100.00%	100.00%
Foreign Plan [Member] | Pension Plan [Member] | Real estate and other [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	8.00%	8.00%
Foreign Plan [Member] | Pension Plan [Member] | Fixed income securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	55.00%	44.00%
Foreign Plan [Member] | Pension Plan [Member] | Equity securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	37.00%	48.00%
Minimum [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 15.0
Minimum [Member] | Domestic Plan [Member] | Pension Plan [Member] | Real estate and other [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%
Minimum [Member] | Domestic Plan [Member] | Pension Plan [Member] | Fixed income securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	45.00%
Minimum [Member] | Domestic Plan [Member] | Pension Plan [Member] | Equity securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25.00%
Minimum [Member] | Foreign Plan [Member] | Pension Plan [Member] | Real estate and other [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0.00%
Minimum [Member] | Foreign Plan [Member] | Pension Plan [Member] | Fixed income securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	43.00%
Minimum [Member] | Foreign Plan [Member] | Pension Plan [Member] | Equity securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	30.00%
Maximum [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	$ 25.0
Maximum [Member] | Domestic Plan [Member] | Pension Plan [Member] | Real estate and other [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	15.00%
Maximum [Member] | Domestic Plan [Member] | Pension Plan [Member] | Fixed income securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	65.00%
Maximum [Member] | Domestic Plan [Member] | Pension Plan [Member] | Equity securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	45.00%
Maximum [Member] | Foreign Plan [Member] | Pension Plan [Member] | Real estate and other [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	10.00%
Maximum [Member] | Foreign Plan [Member] | Pension Plan [Member] | Fixed income securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	65.00%
Maximum [Member] | Foreign Plan [Member] | Pension Plan [Member] | Equity securities [Member]
Defined Benefit Plan, Plan Assets, Allocations [Abstract]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	56.00%