CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Current assets
Cash and cash equivalents	$ 158,092	$ 225,477
Accounts receivable, net	32,641	35,380
Inventories, net	32,733	39,883
Other receivables	4,295	7,847
Prepaid expenses	7,390	10,560
Hedge collateral (Note 9)	1,000	2,940
Other current assets (Note 1)	9,283	15,766
Total current assets	245,434	337,853
Property, plant and equipment, net	100,122	110,747
Operating lease right-of-use assets	4,639	5,265
Intangible assets, net	1,537	1,930
Long-term prepaid expenses	5,736	10,939
Deferred income taxes (Note 16)	50,836	38,324
Other non-current assets	12,187	11,587
Total assets	420,491	516,645
Current liabilities
Accounts payable	24,443	17,998
Other accounts payable	5,292	9,702
Accrued expenses	10,457	9,688
Accrued income taxes	1,496	3,154
Operating lease liabilities	1,914	1,397
Other current liabilities (Note 1)	3,286	5,306
Total current liabilities	46,888	47,245
Accrued severance benefits, net	16,020	23,121
Non-current operating lease liabilities	2,897	4,091
Other non-current liabilities	10,088	14,035
Total liabilities	75,893	88,492
Commitments and contingencies
Stockholders' equity
Common stock, $0.01 par value, 150,000,000 shares authorized, 56,971,394 shares issued and 38,852,742 outstanding at December 31, 2023 and 56,432,449 shares issued and 43,824,575 outstanding at December 31, 2022	569	564
Additional paid-in capital	273,256	266,058
Retained earnings	298,884	335,506
Treasury stock, 18,118,652 shares at December 31, 2023 and 12,607,874 shares at December 31, 2022, respectively	(213,454)	(161,422)
Accumulated other comprehensive loss	(14,657)	(12,553)
Total stockholders' equity	344,598	428,153
Total liabilities and stockholders' equity	$ 420,491	$ 516,645