Cumulative change in ownership percentage.

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Deferred tax assets tax credit carry forwards research begin to expire.

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Operating loss carryforwards expiration year.

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Percentage of loss carryforwards offset through future taxable income.

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Period for cumulative change In ownership.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

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

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

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

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

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The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

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The increase (decrease) during the reporting period in the account that represents the temporary difference that results from Income or Loss that is recognized for accounting purposes but not for tax purposes and vice versa.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Description of the limitation related to use of the tax credit carryforward.

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No definition available.

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Income Taxes - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating Loss Carryforwards [Line Items]
Federal operating loss carryforwards	$ 8,700,000
State operating loss carryforwards	10,900,000
Domestic operating loss carryforwards	100,000
Research and development credit carryforwards	$ 1,788,000	$ 829,000
Operating loss and research and development credit carryforwards, limitations on use	Future utilization of the Company’s NOL and R&D credit carryforwards to offset future taxable income may be subject to a substantial annual limitation as a result of ownership changes that may have occurred or that could occur in the future pursuant to Internal Revenue Code Sections 382 and 383. These ownership changes may limit the amount of NOL and R&D credit carryforwards that can be utilized to offset future taxable income and tax, respectively. In general, an “ownership change” as defined by the tax code results from a transaction or series of transactions over a three-year period resulting in an ownership change of more than 50 percent of the outstanding stock of a company by certain stockholders or public groups.
U.S. federal corporate tax rate	21.00%	35.00%
Reduction in the deferred tax asset balance	$ 1,600,000
Interest and penalties related to income tax matters	$ 0	$ 0	$ 0
Minimum
Operating Loss Carryforwards [Line Items]
Cumulative change in ownership percentage	50.00%
Maximum
Operating Loss Carryforwards [Line Items]
Period for cumulative change in ownership	3 years
California
Operating Loss Carryforwards [Line Items]
Research and development credit carryforwards	$ 900,000
Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards, future taxable income, offset percentage	80.00%
Research and development credit carryforwards	$ 1,400,000
Research and development credit carryforwards, begin to expire	2030
Federal \| Earliest Tax Year
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2035
State \| Earliest Tax Year
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2035