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, 2022			291,249
Balance at beginning 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 beginning of period, treasury stock (in shares) at Jun. 30, 2023							(46,269)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	109,668	109,637			109,637			31
Other comprehensive income (loss)	(15,267)	(15,267)				(15,267)
Treasury stock acquired through surrender of shares for tax withholding (in shares)							(111)
Treasury stock acquired through surrender of shares for tax withholding	(2,823)	(2,823)					$ (2,823)
Issuance of stock through share-based compensation plans (in shares)			709
Issuance of stock through share-based compensation plans	1,925	1,925	$ 1	1,924
Share-based compensation	6,787	6,787		6,787
Cash Dividends declared	(36,861)	(36,861)			(36,861)
Subsidiary dividends to non-controlling interests	(271)							(271)
Balance at end of period, common stock (in shares) at Jun. 30, 2023			291,958
Balance at end of period at Jun. 30, 2023	3,762,859	3,732,150	$ 292	2,005,055	1,947,420	1,432	$ (222,049)	30,709
Balance at end of period, treasury stock (in shares) at Dec. 31, 2022							(46,158)
Balance at beginning of period, common stock (in shares) at Mar. 31, 2023			291,814
Balance at beginning of period at Mar. 31, 2023	3,727,163	3,696,477	$ 292	2,001,575	1,901,569	15,090	$ (222,049)	30,686
Balance at beginning of period, treasury stock (in shares) at Jun. 30, 2023							(46,269)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	64,444	64,286			64,286			158
Other comprehensive income (loss)	(13,658)	(13,658)				(13,658)
Issuance of stock through share-based compensation plans (in shares)			144
Issuance of stock through share-based compensation plans	401	401		401
Share-based compensation	3,079	3,079		3,079
Cash Dividends declared	(18,435)	(18,435)			(18,435)
Subsidiary dividends to non-controlling interests	(135)							(135)
Balance at end of period, common stock (in shares) at Jun. 30, 2023			291,958
Balance at end of period at Jun. 30, 2023	$ 3,762,859	3,732,150	$ 292	2,005,055	1,947,420	1,432	$ (222,049)	30,709
Balance at end of period, treasury stock (in shares) at Mar. 31, 2023							(46,269)
Balance at beginning of period, common stock (in shares) at Dec. 31, 2023	245,888		292,167
Balance at beginning of period at Dec. 31, 2023	$ 3,995,035	3,962,308	$ 292	2,008,170	2,159,831	16,350	$ (222,335)	32,727
Balance at beginning of period, treasury stock (in shares) at Jun. 30, 2024	(46,340)						(46,340)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 127,044	125,794			125,794			1,250
Other comprehensive income (loss)	(12,136)	(12,136)				(12,136)
Treasury stock acquired through surrender of shares for tax withholding (in shares)							(61)
Treasury stock acquired through surrender of shares for tax withholding	(1,822)	(1,822)					$ (1,822)
Issuance of stock through share-based compensation plans (in shares)			475
Issuance of stock through share-based compensation plans	2,815	2,815	$ 1	2,814
Share-based compensation	11,528	11,528		11,528
Cash Dividends declared	(38,830)	(38,830)			(38,830)
Subsidiary dividends to non-controlling interests	$ (300)							(300)
Balance at end of period, common stock (in shares) at Jun. 30, 2024	246,302		292,642
Balance at end of period at Jun. 30, 2024	$ 4,083,334	4,049,657	$ 293	2,022,512	2,246,795	4,214	$ (224,157)	33,677
Balance at end of period, treasury stock (in shares) at Dec. 31, 2023	(46,279)						(46,279)
Balance at beginning of period, common stock (in shares) at Mar. 31, 2024			292,494
Balance at beginning of period at Mar. 31, 2024	$ 4,030,608	3,997,127	$ 292	2,014,782	2,199,300	6,910	$ (224,157)	33,481
Balance at beginning of period, treasury stock (in shares) at Jun. 30, 2024	(46,340)						(46,340)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 67,258	66,897			66,897			361
Other comprehensive income (loss)	(2,696)	(2,696)				(2,696)
Issuance of stock through share-based compensation plans (in shares)			148
Issuance of stock through share-based compensation plans	1,460	1,460	$ 1	1,459
Share-based compensation	6,271	6,271		6,271
Cash Dividends declared	(19,402)	(19,402)			(19,402)
Subsidiary dividends to non-controlling interests	$ (165)							(165)
Balance at end of period, common stock (in shares) at Jun. 30, 2024	246,302		292,642
Balance at end of period at Jun. 30, 2024	$ 4,083,334	$ 4,049,657	$ 293	$ 2,022,512	$ 2,246,795	$ 4,214	$ (224,157)	$ 33,677
Balance at end of period, treasury stock (in shares) at Mar. 31, 2024							(46,340)