Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income	$ 92,897	$ 54,486	$ 213,534	$ 22,812
Other comprehensive income (loss), net of tax:
Adjustments to net unrealized gains (losses) on available-for-sale debt investments	(165)	0	193	0
Adjustments to unrealized components of defined benefit pension plans	11	(125)	34	(314)
Foreign currency translation	4,191	51	3,967	3,745
Total other comprehensive income (loss)	4,037	(74)	4,194	3,431
Comprehensive income	96,934	54,412	217,728	26,243
Comprehensive income attributable to non-controlling interests	(746)	(416)	(2,070)	(1,071)
Comprehensive income attributable to Amkor	$ 96,188	$ 53,996	$ 215,658	$ 25,172

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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