Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Net income	$ 29,697us-gaap_ProfitLoss	$ 21,183us-gaap_ProfitLoss
Other comprehensive income, net of tax:
Adjustments to unrealized components of defined benefit pension plans, net of tax	22	120
Foreign currency translation adjustment	(122)	685
Equity interest in J-Devices' other comprehensive income, net of tax	1,338	3,144
Total other comprehensive income	1,238	3,949
Comprehensive income	30,935	25,132
Comprehensive income attributable to noncontrolling interests	(916)	(550)
Comprehensive income attributable to Amkor	$ 30,019us-gaap_ComprehensiveIncomeNetOfTax	$ 24,582us-gaap_ComprehensiveIncomeNetOfTax

Other Comprehensive Income (Loss), Portion Attributable to Equity Method Investment, Net of Tax

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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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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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