Accrued Expenses (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Payroll and benefits	$ 62,626	$ 77,635
Deferred revenue and customer advances	59,171	56,829
Income taxes payable	38,072us-gaap_AccruedIncomeTaxesCurrent	31,580us-gaap_AccruedIncomeTaxesCurrent
Accrued interest	36,995us-gaap_InterestPayableCurrent	15,947us-gaap_InterestPayableCurrent
Accrued settlement costs (Note 17)	31,006amkr_Accruedsettlementcostscurrent	32,414amkr_Accruedsettlementcostscurrent
Accrued severance plan obligations (Note 15)	13,809	13,226
Other accrued expenses	30,941us-gaap_OtherAccruedLiabilitiesCurrent	31,366us-gaap_OtherAccruedLiabilitiesCurrent
Total accrued expenses	$ 272,620us-gaap_AccruedLiabilitiesCurrent	$ 258,997us-gaap_AccruedLiabilitiesCurrent

Accrued settlement costs, current

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Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Total carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue or other forms of income in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer.

+ References

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-Publisher FASB

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-Name Staff Accounting Bulletin (SAB)

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Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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Carrying value as of the balance sheet date of obligations incurred through that date and payable arising from transactions not otherwise specified in the taxonomy. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Liability for amount due employees, in addition to wages and any other money that employers owe employees, when their employment ends through a layoff or other termination. For example, a company may provide involuntarily terminated employees with a lump sum payment equal to one week's salary for every year of employment.

+ References

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-Publisher FASB

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-Glossary Other Postemployment Benefits

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