Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
COMPREHENSIVE INCOME (LOSS):
Net income	$ 149,213	$ 46,196	$ 259,811	$ 136,111
Other comprehensive income (loss):
Foreign currency translation adjustments, net of tax	4,398	6,534	(4,439)	(7,166)
Foreign defined benefit plans, net of tax	39	0	79	0
Total other comprehensive income (loss)	4,437	6,534	(4,360)	(7,166)
Total comprehensive income (loss)	$ 153,650	$ 52,730	$ 255,451	$ 128,945