Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 56,140	$ (9,006)	$ 120,637	$ (31,674)
Other comprehensive income (loss), net of tax:
Adjustments to net unrealized gains (losses) on available-for-sale debt investments	251	0	358	0
Adjustments to unrealized components of defined benefit pension plans	11	(57)	23	(189)
Foreign currency translation	(699)	5,918	(224)	3,694
Total other comprehensive income (loss)	(437)	5,861	157	3,505
Comprehensive income (loss)	55,703	(3,145)	120,794	(28,169)
Comprehensive income attributable to non-controlling interests	(716)	(444)	(1,324)	(655)
Comprehensive income (loss) attributable to Amkor	$ 54,987	$ (3,589)	$ 119,470	$ (28,824)

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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