CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ 149,105	$ (74,099)	$ 199,930	$ (183,712)
Other comprehensive income (loss):
Changes in cumulative translation adjustment and unrealized losses from cash flow hedges	9,551	7,878	18,491	(76,742)
Amortization of pension and postretirement items	6,951	7,371	13,967	15,150
Income tax expense related to amortization of pension and postretirement items	(1,453)	(1,492)	(2,971)	(3,105)
Amortization of pension and postretirement items, net of taxes	5,498	5,879	10,996	12,045
Change in net actuarial loss and prior service cost	116	(4,539)	116	(4,539)
Income tax (expense) benefit related to change in net actuarial loss and prior service cost	(80)	1,087	(80)	1,087
Change in net actuarial loss and prior service cost, net of taxes	36	(3,452)	36	(3,452)
Other comprehensive income (loss), net of taxes	15,085	10,305	29,523	(68,149)
Comprehensive income (loss)	$ 164,190	$ (63,794)	$ 229,453	$ (251,861)