Loss Contingency, Interest Rate After Date of Award

No definition available.

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- Definition

Number of Quarterly Settlement Payments

+ References

No definition available.

+ Details

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Namespace Prefix:	amkr_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

+ Details

Name:	us-gaap_LitigationReserve
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Interest expense (income) directly attributable to an award in settlement of litigation.

+ References

No definition available.

+ Details

Name:	us-gaap_LitigationSettlementInterest
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_LossContingenciesLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of damages awarded to the plaintiff in the legal matter.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14435-108349

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 450

-SubTopic 20

-Section 50

-Paragraph 9

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14557-108349

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Minimum amount of other commitment not otherwise specified in the taxonomy. Excludes commitments explicitly modeled in the taxonomy, including but not limited to, long-term and short-term purchase commitments, recorded and unrecorded purchase obligations, supply commitments, registration payment arrangements, leases, debt, product warranties, guarantees, environmental remediation obligations, and pensions.

+ References

No definition available.

+ Details

Name:	us-gaap_OtherCommitment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_CostOfSalesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_InterestExpenseMember
Namespace Prefix:
Data Type:	na
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Period Type:

- Details

Name:	us-gaap_LitigationCaseAxis=amkr_TesseraIncLegalProceedingsMember
Namespace Prefix:
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- Details

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Commitments and Contingencies (Details) (USD $)	1 Months Ended		3 Months Ended	48 Months Ended
Commitments and Contingencies (Details) (USD $)	Oct. 31, 2014	May 31, 2014	Dec. 31, 2014	Dec. 31, 2018	Oct. 01, 2014	Sep. 30, 2014
Loss Contingencies [Line Items]
Other Commitment			$ 19,400,000us-gaap_OtherCommitment
Tessera Inc Legal Proceedings [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Awarded, Value	128,000,000	113,000,000
Loss Contingency, Interest Rate Post-Judgment					10.00%
Litigation Settlement, Expense			87,100,000
Liabilities			136,900,000
Tessera Inc Legal Proceedings [Member] \| Subsequent Event [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Amount				155,000,000
Number of Quarterly Settlement Payments				16
Litigation Settlement Interest				18,100,000
Cost of Sales [Member] \| Tessera Inc Legal Proceedings [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Expense			75,300,000
Interest Expense [Member] \| Tessera Inc Legal Proceedings [Member]
Loss Contingencies [Line Items]
Litigation Settlement, Expense			11,800,000
Letter of Credit [Member]
Loss Contingencies [Line Items]
Credit facility, borrowing capacity			25,000,000.0
Available letter of credit subfacility utilized			400,000
Letter of credit sublimit facility remaining			24,600,000
Line of Credit [Member] \| $200 million revolving credit facility, LIBOR plus 1.25%-1.75%, due December 2019 (1) \| Revolving Credit Facility [Member]
Loss Contingencies [Line Items]
Credit facility, borrowing capacity			$ 200,000,000			$ 150,000,000