Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Net sales	$ 1,065,684	$ 1,008,385	$ 2,091,003	$ 1,907,669
Cost of sales	895,967	831,769	1,763,515	1,594,819
Gross profit	169,717	176,616	327,488	312,850
Selling, general and administrative	74,700	67,785	155,423	144,067
Research and development	41,076	44,281	82,005	85,849
Gain on sale of real estate	0	(108,109)	0	(108,109)
Total operating expenses	115,776	3,957	237,428	121,807
Operating income	53,941	172,659	90,060	191,043
Interest expense	21,127	22,158	41,138	43,412
Interest expense, related party	0	293	0	1,535
Other (income) expense, net	(11,001)	(3,288)	(7,569)	7,893
Total other expense, net	10,126	19,163	33,569	52,840
Income before taxes	43,815	153,496	56,491	138,203
Income tax expense	10,631	33,466	13,112	32,141
Net income	33,184	120,030	43,379	106,062
Net income attributable to non-controlling interests	(593)	(1,017)	(1,244)	(1,835)
Net income attributable to Amkor	$ 32,591	$ 119,013	$ 42,135	$ 104,227
Net income attributable to Amkor per common share:
Basic (in dollars per share)	$ 0.14	$ 0.50	$ 0.18	$ 0.44
Diluted (in dollars per share)	$ 0.14	$ 0.50	$ 0.18	$ 0.44
Shares used in computing per common share amounts:
Basic (in shares)	239,351	238,863	239,283	238,774
Diluted (in shares)	239,804	239,679	239,805	239,601