Employee and Retiree Benefit Plans (Fair Value Measurements of Retirement Plan Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 487,094	$ 563,825
Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	86,885	97,758
Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	365,154	428,117
Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	35,055	37,950
United States [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	316,543	351,292
United States [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	86,885	97,758
United States [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	194,603	215,584
United States [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	35,055	37,950
United States [Member] | Defined Benefit Plan, Equity Securities, US Core [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	62,105	67,343
United States [Member] | Defined Benefit Plan, Equity Securities, US Core [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	62,105	67,343
United States [Member] | Defined Benefit Plan, Equity Securities, US Small/Midcap [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	19,436	24,544
United States [Member] | Defined Benefit Plan, Equity Securities, US Small/Midcap [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	19,436	24,544
United States [Member] | Defined Benefit Plan, Equity Securities, Hedged Funds And Other Alternative Strategies [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	45,844	50,522
United States [Member] | Defined Benefit Plan, Equity Securities, Hedged Funds And Other Alternative Strategies [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	10,789	12,572
United States [Member] | Defined Benefit Plan, Equity Securities, Hedged Funds And Other Alternative Strategies [Member] | Level 3 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	35,055	37,950
United States [Member] | Defined Benefit Plan, Equity Securities, International Commingled Trust Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	63,089	83,960
United States [Member] | Defined Benefit Plan, Equity Securities, International Commingled Trust Fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	63,089	83,960
United States [Member] | Defined Benefit Plan, Equity Securities, Emerging Market Commingled Equity Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	15,355	20,774
United States [Member] | Defined Benefit Plan, Equity Securities, Emerging Market Commingled Equity Fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	15,355	20,774
United States [Member] | Defined Benefit Plan, Fixed Income Securities, US Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	87,526	79,890
United States [Member] | Defined Benefit Plan, Fixed Income Securities, US Fixed Income [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	87,526	79,890
United States [Member] | Defined Benefit Plan, Fixed Income Securities, International Commingled Trust Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	13,274	13,122
United States [Member] | Defined Benefit Plan, Fixed Income Securities, International Commingled Trust Fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	13,274	13,122
United States [Member] | Defined Benefit Plan, Fixed Income Securities, Emerging Market Mutual Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	4,570	5,266
United States [Member] | Defined Benefit Plan, Fixed Income Securities, Emerging Market Mutual Fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	4,570	5,266
United States [Member] | Defined Benefit Plan, Cash And Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	5,344	5,871
United States [Member] | Defined Benefit Plan, Cash And Equivalents [Member] | Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	5,344	5,871
Foreign Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	170,551	212,533
Foreign Plans [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	170,551	212,533
Foreign Plans [Member] | Defined Benefit Plan, Cash And Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	3,207	6,888
Foreign Plans [Member] | Defined Benefit Plan, Cash And Equivalents [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	3,207	6,888
Foreign Plans [Member] | Defined Benefit Plan, Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	67,165	78,666
Foreign Plans [Member] | Defined Benefit Plan, Equity Securities [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	67,165	78,666
Foreign Plans [Member] | Defined Benefit Plan, Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	89,417	103,314
Foreign Plans [Member] | Defined Benefit Plan, Fixed Income Securities [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	89,417	103,314
Foreign Plans [Member] | Defined Benefit Plan, Diversified Pooled Fund [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	10,762	23,665
Foreign Plans [Member] | Defined Benefit Plan, Diversified Pooled Fund [Member] | Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value of Plan Assets	$ 10,762	$ 23,665