Employee and Retiree Benefit Plans - Amount Related to Foreign Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at December 31	$ 586,720	$ 547,484
Foreign Plans
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at December 31	221,463	197,965
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at December 31	981,467	883,269	$ 777,645
Fair value of plan assets at December 31	586,720	547,484	487,094
Net plan liabilities recognized	(394,747)	(335,785)
Net periodic benefit expense (benefit)	37,266	25,150	28,840
Pension Benefits | Foreign Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at December 31	230,101	209,923
Fair value of plan assets at December 31	221,463	197,965
Net plan liabilities recognized	(8,638)	(11,957)
Net periodic benefit expense (benefit)	437	(933)
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at December 31	108,378	108,401	94,779
Fair value of plan assets at December 31	0	0	0
Net plan liabilities recognized	(108,378)	(108,401)
Net periodic benefit expense (benefit)	2,143	5,230	$ 5,354
Other Postretirement Benefits | Foreign Plans
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at December 31	492	387
Fair value of plan assets at December 31	0	0
Net plan liabilities recognized	492	387
Net periodic benefit expense (benefit)	$ 46	$ 147