Employee Retirement Plans (Weighted-average Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit Cost) (Details)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.33%	3.63%	4.07%
Discount rate	3.63%	4.06%	4.31%
United States [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.28%	3.58%	4.01%
Rate of compensation increase	3.50%	3.50%	3.50%
Discount rate	3.58%	4.01%	4.24%
Expected return on plan assets	6.00%	6.00%	6.00%
Rate of compensation increase	3.50%	3.50%	3.50%
International [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Discount rate	1.96%	1.93%	2.29%
Rate of compensation increase	2.96%	2.81%	3.97%
Discount rate	1.93%	2.29%	3.23%
Expected return on plan assets	2.13%	3.97%	3.92%
Rate of compensation increase	2.81%	2.06%	2.89%