Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net income	$ 133,887us-gaap_ProfitLoss	$ 111,657us-gaap_ProfitLoss	$ 42,702us-gaap_ProfitLoss
Other comprehensive (loss) income, net of tax:
Adjustments to unrealized components of defined benefit pension plans, net of tax	(1,512)	4,360	5,137
Foreign currency translation adjustment	(11,964)	(4,895)	(2,688)
Equity interest in J-Devices' other comprehensive loss, net of tax	(19,136)	(10,961)	(2,057)
Total other comprehensive (loss) income	(32,612)	(11,496)	392
Comprehensive income	101,275	100,161	43,094
Comprehensive income attributable to noncontrolling interests	3,501	2,361	884
Comprehensive income attributable to Amkor	$ 97,774us-gaap_ComprehensiveIncomeNetOfTax	$ 97,800us-gaap_ComprehensiveIncomeNetOfTax	$ 42,210us-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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