Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Income Taxes And Tax Related [Line Items]
Statutory federal income tax rate	34.00%
Federal and State [Member]
Income Taxes And Tax Related [Line Items]
Net operating loss carryforwards	136.6
Tax credit carryforwards	2.3
Earliest Tax Year [Member]
Income Taxes And Tax Related [Line Items]
Operating loss carryforwards expiration year	2023
Open for examination	2004
Latest Tax Year [Member]
Income Taxes And Tax Related [Line Items]
Operating loss carryforwards expiration year	2033

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Net Operating Loss Carry Forwards Expiration Year

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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