Pension and Postretirement Benefit Plans - Significant Weighted Average Assumptions Used in Measurement of OPEB Obligations (Details) - Other Postretirement Benefits Plan [Member] - Foreign Plan [Member]	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
OPEB benefit obligations:
Discount rate	3.71%	3.41%	3.69%
Net periodic benefit cost:
Discount rate	3.42%	3.70%	3.45%
Initial health care cost trend rate	4.12%	5.07%	5.32%
Ultimate health care cost trend rate	5.10%	5.07%	5.02%
Year ultimate reached	2023	2018	2018