Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Dilutive Securities Adjustments [Line Items]
Net income (loss) attributable to Amkor	$ (875)	$ 28,781
Income allocated to participating securities	0	(68)
Net income (loss) available to Amkor common stockholders	$ (875)	$ 28,713
Adjustment for dilutive securities on net income:
Weighted average shares outstanding — basic	237,025	236,708
Effect of dilutive securities:
Stock options and restricted share awards	0	716
Weighted average shares outstanding — diluted	237,025	237,424
Net income attributable to Amkor per common share:
Basic (in dollars per share)	$ 0.00	$ 0.12
Diluted (in dollars per share)	$ 0.00	$ 0.12

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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