Revision of Previously Reported Financial Information Statement of Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income	$ 5,366		$ 7,950	$ 4,961	$ 35,464
Equity interest in J-Devices' other comprehensive loss, net of tax	0		(5,245)	0	(3,885)
Foreign currency translation	26,955	$ 19,323	10	46,278	(112)
Total other comprehensive loss	26,978	19,347	(5,213)	46,325	(3,953)
Comprehensive income	32,344	18,942	2,737	51,286	31,511
Comprehensive income attributable to Amkor	$ 31,691	18,472	2,114	$ 50,163	29,972
Previously Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income			10,201		39,898
Equity interest in J-Devices' other comprehensive loss, net of tax			(5,388)		(4,050)
Foreign currency translation		19,864
Total other comprehensive loss		19,888	(5,356)		(4,118)
Comprehensive income		19,483	4,845		35,780
Comprehensive income attributable to Amkor		19,013	4,222		34,241
Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Net income			(2,251)		(4,434)
Equity interest in J-Devices' other comprehensive loss, net of tax			143		165
Foreign currency translation		(541)
Total other comprehensive loss		(541)	143		165
Comprehensive income		(541)	(2,108)		(4,269)
Comprehensive income attributable to Amkor		$ (541)	$ (2,108)		$ (4,269)