Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Net sales	$ 2,244,044	$ 2,941,324	$ 2,904,563
Cost of sales	1,851,867	2,392,377	2,266,145
Gross profit	392,177	548,947	638,418
Operating expenses:
Selling, general and administrative	176,857	202,699	261,994
Research and development	84,472	88,573	124,762
Production start-up	90,735	42,643	1,021
Restructuring and asset impairments	0	37,181	743,862
Goodwill impairment	0	0	74,930
Total operating expenses	352,064	371,096	1,206,569
Operating income (loss)	40,113	177,851	(568,151)
Foreign currency loss, net	(570)	(9,640)	(14,007)
Interest income	59,788	35,704	25,193
Interest expense, net	(25,921)	(25,765)	(20,538)
Other income, net	39,737	23,965	40,252
Income (loss) before taxes and equity in earnings	113,147	202,115	(537,251)
Income tax expense	(3,441)	(371,996)	(23,167)
Equity in earnings, net of tax	34,620	4,266	144,306
Net income (loss)	$ 144,326	$ (165,615)	$ (416,112)
Net income (loss) per share:
Basic	$ 1.38	$ (1.59)	$ (4.05)
Diluted	$ 1.36	$ (1.59)	$ (4.05)
Weighted-average number of shares used in per share calculations:
Basic	104,745	104,328	102,866
Diluted	106,113	104,328	102,866