Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 650,274	$ 698,002
Restricted cash	933	1,007
Short-term investments (amortized cost of $163,703 and $133,744 in 2021 and 2020, respectively)	163,693	133,769
Accounts receivable, net of allowances	950,015	962,643
Inventories	307,545	297,293
Other current assets	41,594	40,218
Total current assets	2,114,054	2,132,932
Property, plant and equipment, net	2,623,470	2,566,002
Operating lease right of use assets	141,247	147,236
Goodwill	25,481	27,325
Restricted cash	3,565	3,188
Other assets	145,648	145,628
Total assets	5,053,465	5,022,311
Current liabilities:
Short-term borrowings and current portion of long-term debt	135,405	149,007
Trade accounts payable	602,962	636,434
Capital expenditures payable	273,934	181,339
Accrued expenses	304,556	349,207
Total current liabilities	1,316,857	1,315,987
Long-term debt	952,366	1,005,339
Pension and severance obligations	146,118	159,610
Long-term operating lease liabilities	77,651	84,420
Other non-current liabilities	98,236	102,996
Total liabilities	2,591,228	2,668,352
Commitments and contingencies (Note 15)
Stockholders’ equity:
Preferred stock, $0.001 par value, 10,000 shares authorized, designated Series A, none issued	0	0
Common stock, $0.001 par value, 500,000 shares authorized; 289,865 and 288,923 shares issued; and 243,714 and 242,829 shares outstanding in 2021 and 2020, respectively	290	289
Additional paid-in capital	1,964,331	1,953,378
Retained earnings	672,534	562,502
Accumulated other comprehensive income (loss)	15,823	27,270
Treasury stock, at cost, 46,151 and 46,094 shares in 2021 and 2020, respectively	(219,061)	(217,740)
Total Amkor stockholders’ equity	2,433,917	2,325,699
Non-controlling interests in subsidiaries	28,320	28,260
Total equity	2,462,237	2,353,959
Total liabilities and equity	$ 5,053,465	$ 5,022,311