Pension, Other Postretirement Benefits and Savings Plans - Weighted Average Assumptions Used (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Pension Plan | United States
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate, benefit obligations	2.42%	3.22%
Discount rate for determining interest costs, benefit costs	2.66%	3.85%	3.09%
Expected long term return on plan assets, benefit costs	4.22%	5.25%	4.58%
Pension Plan | Non-U.S.
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate, benefit obligations	1.49%	1.98%
Rate of compensation increase, benefit obligations	2.89%	2.92%
Discount rate for determining interest costs, benefit costs	2.26%	2.84%	2.56%
Expected long term return on plan assets, benefit costs	2.52%	2.95%	3.02%
Rate of compensation increase, benefit cost	2.92%	2.91%	2.91%
Other Postretirement Benefits | United States
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate, benefit obligations	2.34%	3.14%
Discount rate for determining interest costs, benefit costs	2.68%	3.79%	2.99%
Other Postretirement Benefits | Non-U.S.
Defined Benefit Plans And Other Postretirement Benefit Plans Table Text Block [Line Items]
Discount rate, benefit obligations	4.09%	4.39%
Discount rate for determining interest costs, benefit costs	5.68%	6.25%	6.13%