Consolidated Statements of Stockholders' Equity - 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, 2019			286,877
Balance at beginning of period at Dec. 31, 2019	$ 1,990,239	$ 1,963,739	$ 287	$ 1,927,739	$ 234,077	$ 19,115	$ (217,479)	$ 26,500
Balance at beginning of period, treasury stock (in shares) at Dec. 31, 2019							(46,072)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	340,499	338,138			338,138			2,361
Other comprehensive income (loss)	8,155	8,155				8,155
Treasury stock acquired through surrender of shares for tax withholding (in shares)							(22)
Treasury stock acquired through surrender of shares for tax withholding	(261)	(261)					$ (261)
Issuance of stock through share-based compensation plans (in shares)			2,046
Issuance of stock through share-based compensation plans	17,611	17,611	$ 2	17,609
Share-based compensation	8,030	8,030		8,030
Cash dividends declared	(9,713)	(9,713)			(9,713)
Subsidiary dividends to noncontrolling interests	(601)							(601)
Balance at end of period, common stock (in shares) at Dec. 31, 2020			288,923
Balance at end of period at Dec. 31, 2020	2,353,959	2,325,699	$ 289	1,953,378	562,502	27,270	$ (217,740)	28,260
Balance at end of period, treasury stock (in shares) at Dec. 31, 2020							(46,094)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	645,607	642,995			642,995			2,612
Other comprehensive income (loss)	(7,292)	(7,292)				(7,292)
Treasury stock acquired through surrender of shares for tax withholding (in shares)							(57)
Treasury stock acquired through surrender of shares for tax withholding	(1,325)	(1,325)					$ (1,325)
Issuance of stock through share-based compensation plans (in shares)			1,543
Issuance of stock through share-based compensation plans	12,787	12,787	$ 1	12,786
Share-based compensation	10,970	10,970		10,970
Cash dividends declared	(41,558)	(41,558)			(41,558)
Subsidiary dividends to noncontrolling interests	$ (602)							(602)
Balance at end of period, common stock (in shares) at Dec. 31, 2021	290,466		290,466
Balance at end of period at Dec. 31, 2021	$ 2,972,546	2,942,276	$ 290	1,977,134	1,163,939	19,978	$ (219,065)	30,270
Balance at end of period, treasury stock (in shares) at Dec. 31, 2021	(46,151)						(46,151)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 767,042	765,823			765,823			1,219
Other comprehensive income (loss)	(3,279)	(3,279)				(3,279)
Treasury stock acquired through surrender of shares for tax withholding (in shares)							(7)
Treasury stock acquired through surrender of shares for tax withholding	(161)	(161)					$ (161)
Issuance of stock through share-based compensation plans (in shares)			783
Issuance of stock through share-based compensation plans	5,649	5,649	$ 1	5,648
Share-based compensation	13,562	13,562		13,562
Cash dividends declared	(55,118)	(55,118)			(55,118)
Subsidiary dividends to noncontrolling interests	$ (540)							(540)
Balance at end of period, common stock (in shares) at Dec. 31, 2022	291,249		291,249
Balance at end of period at Dec. 31, 2022	$ 3,699,701	$ 3,668,752	$ 291	$ 1,996,344	$ 1,874,644	$ 16,699	$ (219,226)	$ 30,949
Balance at end of period, treasury stock (in shares) at Dec. 31, 2022	(46,158)						(46,158)