Accrued estimate of product returns and related costs.

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- Definition

Summary Of Significant Accounting Policies [Line Items]

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Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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-Publisher FASB
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-Topic 210
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- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income.

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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-Publisher FASB
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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

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Summary of Significant Accounting Policies and Basis of Presentations - Additional Information (Detail) - USD ($)		3 Months Ended		9 Months Ended
	Apr. 13, 2018	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018	Dec. 31, 2017	Jan. 01, 2017
Summary Of Significant Accounting Policies [Line Items]
Inventory, net		$ 0		$ 0			$ 0
Loss on disposal of leasehold improvements	$ 2,000			2,000
Contract with customer, liability, revenue recognized				0
Deferred revenue		11,000		11,000			11,000
Estimated accrued expense for product return related costs							200,000
General and administrative		1,338,000	$ 1,095,000	3,378,000	$ 3,624,000
Accounting Standards Update 2016-09
Summary Of Significant Accounting Policies [Line Items]
Decrease in accumulated deficit						$ 28,000		$ 28,000
Patents
Summary Of Significant Accounting Policies [Line Items]
General and administrative				100,000	$ 300,000
Cash and Cash Equivalents
Summary Of Significant Accounting Policies [Line Items]
Cash equivalents		$ 3,100,000		$ 3,100,000			$ 3,000,000