Components of Deferred Income Taxes (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Deferred tax liabilities:
Intangibles	$ 377	$ 388
Unrealized currency gain		10,892
Total deferred tax liabilities	377us-gaap_DeferredIncomeTaxLiabilities	11,280us-gaap_DeferredIncomeTaxLiabilities
Deferred tax assets:
Net operating loss carryforwards	205,793	166,951
Federal and state tax credit carryovers	32,318	28,645
Depreciation	4,383aria_DeferredTaxAssetsDepreciation	3,607aria_DeferredTaxAssetsDepreciation
Stock-based compensation	12,803	7,780
Other	9,008us-gaap_DeferredTaxAssetsOther	7,977us-gaap_DeferredTaxAssetsOther
Debt-related deductions	934aria_DeferredTaxAssetsDebtRelated
Total deferred tax assets	265,239us-gaap_DeferredTaxAssetsGross	214,960us-gaap_DeferredTaxAssetsGross
Deferred tax assets, net	264,862aria_DeferredTaxAssetsLiabilitiesGross	203,680aria_DeferredTaxAssetsLiabilitiesGross
Valuation allowance	(264,862)	(203,680)
Total deferred taxes	$ 0us-gaap_DeferredTaxAssetsLiabilitiesNet	$ 0us-gaap_DeferredTaxAssetsLiabilitiesNet

Deferred Tax Assets Debt Related

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The sum of tax effects as of the balance sheet date of all future tax deductions arising from depreciation.

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For entities that gross deferred tax assets and tax liabilities, represents the unclassified net amount of deferred tax assets and liabilities as of the balance sheet date, which result from applying the applicable enacted tax rate to net temporary differences and carryforwards pertaining to assets or liabilities.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences not separately disclosed.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible general business tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from unrealized gains on foreign currency transactions.

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