Deferred Tax Liabilities, Subject to Expiration

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- Definition

Effective Income Tax Rate, Continuing Operations, Foreign

+ References

No definition available.

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- Details

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- Definition

Tax Credit Carryforward, Expiration Year

+ References

No definition available.

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- Definition

The tax effect as of the balance sheet date of the amount of excess of tax deductions over gross income in a year which cannot be used on the tax return of a country outside the country of domicile in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 25

-Paragraph 20

-Subparagraph (b)

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 43, 289

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

The tax effect as of the balance sheet date of the amount of future tax deductions arising from all unused tax credit carryforwards which have been reduced by a valuation allowance.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 3

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Carryforwards

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 43

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

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- Definition

A ratio calculated by dividing the reported amount of income tax expense attributable to continuing operations for the period by GAAP-basis pretax income from continuing operations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 12

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-Section S99

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-Subparagraph (SX 210.4-08.(h)(2))

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-Number 109

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

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-Article 4

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- Definition

The sum of domestic, foreign and state and local operating loss carryforwards, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 48

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

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- Definition

The expiration date of each operating loss carryforward included in total operating loss carryforwards, or the applicable range of such expiration dates.

+ References

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- Definition

The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

+ References

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-Publisher FASB

-Name FASB Interpretation (FIN)

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Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Line Items]
Total amount of unrecognized tax benefits that would affect the tax rate if recognized	$ 1,000,000	$ 500,000
Gross liabilities to expire in 2012	48,000
Corporate tax rate	25.00%	25.00%	25.00%
Tax credit carryforwards	6,000	30,000
Ester Neurosciences Ltd
Income Taxes [Line Items]
Net operating losses that are not likely to be realized in the future	12,000,000
Ireland \| Non-Trading Activity
Income Taxes [Line Items]
Corporate tax rate in Ireland for trading and non-trading activities	25.00%
Ireland \| Trading Activity \| Amarin Pharmaceuticals Ireland Limited
Income Taxes [Line Items]
Corporate tax rate in Ireland for trading and non-trading activities	12.50%
Republic of Ireland, United Kingdom and Israel
Income Taxes [Line Items]
Foreign net operating loss carryforwards	175,700,000
U.S. Federal
Income Taxes [Line Items]
Tax credit carryforwards	1,200,000
U.S. Federal \| Ester Neurosciences Ltd \| Minimum
Income Taxes [Line Items]
U.S Federal tax credit carryforwards, expiration date	2028
U.S. Federal \| Ester Neurosciences Ltd \| Maximum
Income Taxes [Line Items]
U.S Federal tax credit carryforwards, expiration date	2030
State
Income Taxes [Line Items]
Tax credit carryforwards	$ 1,400,000
Foreign Country
Income Taxes [Line Items]
Foreign net operating loss carryforwards, expiration date	2011