Pension and Other Post-Retirement Benefits - Weighted Average Asset Allocations of Domestic Funded Plans (Details) - UNITED STATES	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Target allocation, salaried employees	100.00%
Actual plan asset allocations, salaried employees	100.00%	100.00%
Target allocation, hourly employees	100.00%
Actual plan asset allocation, hourly employees	100.00%	100.00%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation, salaried employees	45.60%
Actual plan asset allocations, salaried employees	44.10%	50.70%
Target allocation, hourly employees	32.70%
Actual plan asset allocation, hourly employees	30.30%	39.40%
Debt Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation, salaried employees	51.00%
Actual plan asset allocations, salaried employees	51.80%	44.80%
Target allocation, hourly employees	64.10%
Actual plan asset allocation, hourly employees	64.90%	56.80%
Real Estate [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation, salaried employees	3.40%
Actual plan asset allocations, salaried employees	3.90%	3.70%
Target allocation, hourly employees	3.20%
Actual plan asset allocation, hourly employees	4.70%	3.70%
Cash [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation, salaried employees	0.00%
Actual plan asset allocations, salaried employees	0.20%	0.80%
Target allocation, hourly employees	0.00%
Actual plan asset allocation, hourly employees	0.10%	0.10%