Pension and Other Post Retirement Plans (Details 3) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
UNITED STATES
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	100.00%	100.00%
UNITED STATES | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	$ 41.3
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	43.6
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	45.4
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	47.6
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	49.5
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	269.5
UNITED STATES | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	10.3
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	9.5
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	8.0
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	5.7
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	3.9
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 11.8
UNITED STATES | Defined Benefit Plan, Equity Securities, US [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	26.00%	25.00%
UNITED STATES | Defined Benefit Plan, Equity Securities, US [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	3.00%	4.00%
UNITED STATES | Defined Benefit Plan, Debt Security
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	69.00%	69.00%
UNITED STATES | Defined Benefit Plan, Real Estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	2.00%	2.00%
Belfast | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	$ 61.1
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	62.2
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	63.2
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	64.3
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	65.4
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	344.2
Belfast | Other Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	0.1
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	0.1
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	0.1
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	0.1
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	0.1
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 5.0
Belfast | Defined Benefit Plan, Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	3200.00%
Belfast | Defined Benefit Plan, Debt Security
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	3600.00%
Belfast | Defined Benefit Plan, Real Assets
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	1300.00%
Belfast | Other Debt Obligations
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	1500.00%
Belfast | Money Market Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	400.00%
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	100.00%	100.00%
UNITED KINGDOM | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Expected Future Benefit Payment, Next Twelve Months	$ 0.9
Defined Benefit Plan, Expected Future Benefit Payment, Year Two	0.9
Defined Benefit Plan, Expected Future Benefit Payment, Year Three	0.9
Defined Benefit Plan, Expected Future Benefit Payment, Year Four	0.9
Defined Benefit Plan, Expected Future Benefit Payment, Year Five	1.0
Defined Benefit Plan, Expected Future Benefit Payment, Five Fiscal Years Thereafter	$ 5.1
UNITED KINGDOM | Defined Benefit Plan, Equity Securities
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	15.00%	15.00%
UNITED KINGDOM | Defined Benefit Plan, Debt Security
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	80.00%	80.00%
UNITED KINGDOM | Defined Benefit Plan, Real Estate
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Actual Allocation, Percentage	5.00%	5.00%