Pensions - Schedule of Defined Benefit Pension Cost Assumptions (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Pension benefit obligations discount rate	3.16%	4.30%	3.63%
Interest cost discount rate	2.74%	3.93%	3.23%
Expected return on plan assets, net of administrative expenses	3.73%	3.68%	3.58%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Pension benefit obligations discount rate	2.39%	3.16%
Interest crediting rate	3.00%	3.36%