Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Statement of Comprehensive Income [Abstract]
Net income	$ 126,458	$ 56,140	$ 246,477	$ 120,637
Other comprehensive income (loss), net of tax:
Adjustments to net unrealized gains (losses) on available-for-sale debt investments	(14)	251	(46)	358
Adjustments to unrealized components of defined benefit pension plans	26	11	51	23
Foreign currency translation	278	(699)	(11,162)	(224)
Total other comprehensive income (loss)	290	(437)	(11,157)	157
Comprehensive income	126,748	55,703	235,320	120,794
Comprehensive income attributable to non-controlling interests	(652)	(716)	(862)	(1,324)
Comprehensive income attributable to Amkor	$ 126,096	$ 54,987	$ 234,458	$ 119,470

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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