v3.26.1
CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (Unaudited) - USD ($)
shares in Thousands, $ in Thousands
Total
Total Amkor Stockholders’ Equity
Common Stock
Additional Paid- In Capital
Retained Earnings
Accumulated Other Comprehensive Income (Loss)
Treasury Stock
Noncontrolling Interest in Subsidiaries
Balance at beginning of period, common stock (in shares) at Dec. 31, 2024     293,052          
Balance at beginning of period at Dec. 31, 2024 $ 4,183,165 $ 4,149,545 $ 293 $ 2,031,643 $ 2,335,132 $ 7,510 $ (225,033) $ 33,620
Balance at beginning of period, treasury stock (in shares) at Jun. 30, 2025             (46,435)  
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Net income 76,905 75,545     75,545     1,360
Other comprehensive income (loss) 4,789 4,789       4,789    
Treasury stock acquired through surrender of shares for tax withholding (in shares)             (67)  
Treasury stock acquired through surrender of shares for tax withholding (1,481) (1,481)         $ (1,481)  
Issuance of stock through share-based compensation plans (in shares)     525          
Issuance of stock through share-based compensation plans 902 902 $ 1 901        
Share-based compensation 9,004 9,004   9,004        
Cash dividends declared (40,880) (40,880)     (40,880)      
Subsidiary dividends to non-controlling interests (330)             (330)
Balance at end of period, common stock (in shares) at Jun. 30, 2025     293,577          
Balance at end of period at Jun. 30, 2025 4,232,074 4,197,424 $ 294 2,041,548 2,369,797 12,299 $ (226,514) 34,650
Balance at end of period, treasury stock (in shares) at Dec. 31, 2024             (46,368)  
Balance at beginning of period, common stock (in shares) at Mar. 31, 2025     293,482          
Balance at beginning of period at Mar. 31, 2025 4,190,590 4,156,410 $ 293 2,036,608 2,335,830 10,031 $ (226,352) 34,180
Balance at beginning of period, treasury stock (in shares) at Jun. 30, 2025             (46,435)  
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Net income 55,052 54,417     54,417     635
Other comprehensive income (loss) 2,268 2,268       2,268    
Treasury stock acquired through surrender of shares for tax withholding (in shares)             (8)  
Treasury stock acquired through surrender of shares for tax withholding (162) (162)         $ (162)  
Issuance of stock through share-based compensation plans (in shares)     95          
Issuance of stock through share-based compensation plans 132 132 $ 1 131        
Share-based compensation 4,809 4,809   4,809        
Cash dividends declared (20,450) (20,450)     (20,450)      
Subsidiary dividends to non-controlling interests (165)             (165)
Balance at end of period, common stock (in shares) at Jun. 30, 2025     293,577          
Balance at end of period at Jun. 30, 2025 $ 4,232,074 4,197,424 $ 294 2,041,548 2,369,797 12,299 $ (226,514) 34,650
Balance at end of period, treasury stock (in shares) at Mar. 31, 2025             (46,427)  
Balance at beginning of period, common stock (in shares) at Dec. 31, 2025 247,303   293,756          
Balance at beginning of period at Dec. 31, 2025 $ 4,506,287 4,471,106 $ 294 2,054,051 2,627,038 16,833 $ (227,110) 35,181
Balance at beginning of period, treasury stock (in shares) at Jun. 30, 2026 (46,576)           (46,576)  
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Net income $ 258,835 257,104     257,104     1,731
Other comprehensive income (loss) (1,726) (1,726)       (1,726)    
Treasury stock acquired through surrender of shares for tax withholding (in shares)             (123)  
Treasury stock acquired through surrender of shares for tax withholding (6,068) (6,068)         $ (6,068)  
Issuance of stock through share-based compensation plans (in shares)     806          
Issuance of stock through share-based compensation plans 1,364 1,364 $ 1 1,363        
Share-based compensation 14,126 14,126   14,126        
Cash dividends declared (41,423) (41,423)     (41,423)      
Capped call transactions related to the issuance of convertible senior notes due 2031 (44,071) (44,071)   (44,071)        
Subsidiary dividends to non-controlling interests $ (496)             (496)
Balance at end of period, common stock (in shares) at Jun. 30, 2026 247,986   294,562          
Balance at end of period at Jun. 30, 2026 $ 4,686,828 4,650,412 $ 295 2,025,469 2,842,719 15,107 $ (233,178) 36,416
Balance at end of period, treasury stock (in shares) at Dec. 31, 2025 (46,453)           (46,453)  
Balance at beginning of period, common stock (in shares) at Mar. 31, 2026     294,394          
Balance at beginning of period at Mar. 31, 2026 $ 4,569,142 4,533,511 $ 294 2,060,642 2,689,683 15,277 $ (232,385) 35,631
Balance at beginning of period, treasury stock (in shares) at Jun. 30, 2026 (46,576)           (46,576)  
Increase (Decrease) in Stockholders' Equity [Roll Forward]                
Net income $ 174,869 173,753     173,753     1,116
Other comprehensive income (loss) (170) (170)       (170)    
Treasury stock acquired through surrender of shares for tax withholding (in shares)             (10)  
Treasury stock acquired through surrender of shares for tax withholding (793) (793)         $ (793)  
Issuance of stock through share-based compensation plans (in shares)     168          
Issuance of stock through share-based compensation plans 864 864 $ 1 863        
Share-based compensation 8,035 8,035   8,035        
Cash dividends declared (20,717) (20,717)     (20,717)      
Capped call transactions related to the issuance of convertible senior notes due 2031 (44,071) (44,071)   (44,071)        
Subsidiary dividends to non-controlling interests $ (331)             (331)
Balance at end of period, common stock (in shares) at Jun. 30, 2026 247,986   294,562          
Balance at end of period at Jun. 30, 2026 $ 4,686,828 $ 4,650,412 $ 295 $ 2,025,469 $ 2,842,719 $ 15,107 $ (233,178) $ 36,416
Balance at end of period, treasury stock (in shares) at Mar. 31, 2026             (46,566)