Earnings Per Share - Schedule of computation of basic and diluted earnings per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Earnings Per Share [Abstract]
Net income attributable to Amkor common stockholders, basic	$ 66,897	$ 64,286	$ 125,794	$ 109,637
Net income attributable to Amkor common stockholders, diluted	$ 66,897	$ 64,286	$ 125,794	$ 109,637
Weighted-average number of common shares outstanding - basic (in shares)	246,228	245,637	246,118	245,485
Effect of dilutive securities:
Share-based awards (in shares)	1,632	1,327	1,672	1,561
Weighted-average number of common shares outstanding - diluted (in shares)	247,860	246,964	247,790	247,046
Net income attributable to Amkor per common share:
Basic (in dollars per share)	$ 0.27	$ 0.26	$ 0.51	$ 0.45
Diluted (in dollars per share)	$ 0.27	$ 0.26	$ 0.51	$ 0.44