Adjustments To Additional Paid In Capital Reclassification Excercise Of Stock Option

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Operating loss carryforward expiration period description.

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Operating Loss Carryforwards Exercise Of Stock Options

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The amount of estimated interest recognized in the period arising from income tax examinations.

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

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Income Taxes - Additional Information (Detail) (USD $)	12 Months Ended
Income Taxes - Additional Information (Detail) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Contingency [Line Items]
Unrecognized tax benefits	$ 0us-gaap_UnrecognizedTaxBenefits		$ 0us-gaap_UnrecognizedTaxBenefits
Increase in valuation allowances	10,657,000	10,270,000
Tax liabilities	0us-gaap_DeferredIncomeTaxLiabilities
Tax related interest	0
Tax related penalties	0
Domestic Tax Authority [Member]
Income Tax Contingency [Line Items]
Net operating loss carry forward	158,465,000
Operating loss carryforward expiration period description	2018 through 2034
Excess deductions from exercise of stock option	1,792,000
State and Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Net operating loss carry forward	40,241,000
Operating loss carryforward expiration period description	2015 through 2034
Operating loss carry forward for the exercise of stock	1,362,000
Foreign Tax Authority [Member]
Income Tax Contingency [Line Items]
Net operating loss carry forward	8,208,000
Capital Loss Carryforward [Member] \| Domestic And State [Member]
Income Tax Contingency [Line Items]
Operating loss carryforward expiration period description	2015 through 2016
Capital loss carry forward for federal and state income tax purposes	746,000
Research and Development [Member] \| Domestic Tax Authority [Member]
Income Tax Contingency [Line Items]
Operating loss carryforward expiration period description	2018 through 2034
Capital loss carry forward for federal and state income tax purposes	6,178,000
Research and Development [Member] \| State and Local Jurisdiction [Member]
Income Tax Contingency [Line Items]
Capital loss carry forward for federal and state income tax purposes	5,484,000
State research and development tax credits net of federal tax effect	$ 3,619,000