Income Tax Benefit Recognition Criteria Percentage Threshold

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Number Of Customer Accounted For Ten Percent Or More Of Accounts Receivable

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Number Of Customer Accounted For Ten Percent Or More Of Revenue

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Shipping And Handling Costs

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- Definition

Significant Accounting Policies.

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No definition available.

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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-Publisher FASB
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-Topic 720
-SubTopic 35
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-Paragraph 1
-Subparagraph (b)
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- Definition

Amount of allowance for credit loss on accounts receivable.

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Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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.

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No definition available.

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- Definition

Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount of liability for consideration received or receivable from customer which is not included in transaction price, when consideration is expected to be refunded to customer.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Section 55
-Paragraph 27
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- Definition

Specific incremental costs directly attributable to a proposed or actual offering of securities which are deferred at the end of the reporting period.

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- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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No definition available.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended		39 Months Ended
	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($) Segment	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2018 USD ($)
Significant Accounting Policies [Line Items]
Allowance for doubtful accounts					$ 0	$ 500
Income tax benefit recognition, minimum percentage of likelihood being realized			50.00%
Revenues	$ 40,603	$ 24,672	$ 88,817	$ 53,576	73,279	36,459	$ 6,200
Deferred offering costs					1,218
Number of reportable segments \| Segment			1
Level 2 \| Horizon Term Loan
Significant Accounting Policies [Line Items]
Fair value of borrowings	14,700		$ 14,700		14,700
Level 1
Significant Accounting Policies [Line Items]
Cash and restricted cash	36,100		36,100		20,700	5,800
Shipping and Handling
Significant Accounting Policies [Line Items]
Revenues	0	$ 0	100		0	100
Maximum \| Shipping and Handling
Significant Accounting Policies [Line Items]
Revenues				$ 100
Accrued Liabilities
Significant Accounting Policies [Line Items]
Refund liabilities for sales returns	$ 500		$ 500		300	200
Prepaid Expenses and Other Current Assets
Significant Accounting Policies [Line Items]
Restricted cash deposit associated with credit facility					600	300
Deferred offering costs					1,200	0
Other Noncurrent Assets
Significant Accounting Policies [Line Items]
Restricted cash deposit associated with credit facility					100	300
Sales and distribution expenses
Significant Accounting Policies [Line Items]
Advertising cost					4,500	2,900
Shipping and handling cost					11,400	8,200
Other Expense, Net \| Maximum
Significant Accounting Policies [Line Items]
Net loss from foreign currency transactions					$ (100)	$ (100)
Customer Concentration Risk \| Revenue Benchmark
Significant Accounting Policies [Line Items]
Number of customers accounted					0	0
Customer Concentration Risk \| Revenue Benchmark \| Amazon
Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk					95.00%	98.00%
Customer Concentration Risk \| Accounts Receivable
Significant Accounting Policies [Line Items]
Number of customers accounted					0	0
Customer Concentration Risk \| Accounts Receivable \| Amazon
Significant Accounting Policies [Line Items]
Percentage of concentration of credit risk					79.00%	90.00%