Estimated capital expenditure.

No definition available.

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- Definition

line of credit facility borrowing base as a percentage of accounts receivable.

+ References

No definition available.

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- Definition

Period within which aging report shall be delivered after the end of each month.

+ References

No definition available.

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- Definition

Period within which annual audited statements shall be delivered.

+ References

No definition available.

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- Definition

Period within which borrowing base report shall be delivered at the end of each month.

+ References

No definition available.

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- Definition

Period within which monthly unaudited statements shall be delivered.

+ References

No definition available.

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- Definition

Period within which quarterly unaudited statements shall be delivered.

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No definition available.

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- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

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-Publisher FASB
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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

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Balance Type:	credit
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- Definition

The average effective interest rate during the reporting period.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Period Type:	instant

- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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Period Type:	duration

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

+ References

+ Details

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Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of the frequency of periodic payments, which may be presented in a variety of ways (for example, monthly, quarterly, annually).

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maturity date of long-term debt, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

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Debt - Additional Information (Detail) - USD ($)			3 Months Ended	9 Months Ended		12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Oct. 23, 2020	Sep. 21, 2017	Dec. 31, 2017	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 22, 2016
Debt Instrument [Line Items]
Amortization of debt issuance costs				$ 118	$ 151	$ 220	$ 264
Revolving Credit Facility [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Period within which annual audited statements shall be delivered						180 days
Period within which monthly unaudited statements shall be delivered						30 days
Interest expenses on the revolving credit facility				0	0	$ 0	0
Line of credit				$ 0	$ 0	$ 0	$ 0
Period within which borrowing base report shall be delivered after the end of each month						30 days
Period within which aging report shall be delivered after the end of each month						30 days
Credit Agreement
Debt Instrument [Line Items]
Debt issuance costs gross								$ 1,220
Debt instrument effective interest rate percentage				10.60%	10.60%	10.60%	10.60%
Period within which annual audited statements shall be delivered				120 days		120 days
Period within which quarterly unaudited statements shall be delivered				45 days		45 days
Period within which monthly unaudited statements shall be delivered				30 days		30 days
Estimated capital expenditure				$ 500		$ 500
Credit Agreement \| Term Loan
Debt Instrument [Line Items]
Long term debt variable interest rate percentage						0.50%
Debt instrument face value								48,500
Long term debt date of maturity						Dec. 22, 2021
Credit Agreement \| Term Loan \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument variable interest rate spread						8.50%
Credit Agreement \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt variable interest rate percentage						0.50%
Line of credit maximum borrowing capacity								$ 5,000
Line of credit facility, expiration date						Dec. 22, 2021
Credit Agreement \| Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Debt instrument variable interest rate spread						8.50%
Loan And Security Agreement [Member] \| Revolving Credit Facility [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity		$ 8,000
Line of credit facility, expiration date		Sep. 21, 2019
Debt instrument variable interest rate spread			2.50%
Line of credit facility frequency of payments		monthly
Line of credit facility borrowing base percentage		80.00%
Loan And Security Agreement [Member] \| Letter of Credit \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Line of credit maximum borrowing capacity		$ 2,775
Loan And Security Sixth Amendment Agreement [Member] \| Revolving Credit Facility [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Line of credit facility, expiration date	Jul. 31, 2021
Loan And Security Sixth Amendment Agreement [Member] \| Revolving Credit Facility [Member] \| Silicon Valley Bank [Member] \| Streamline Period
Debt Instrument [Line Items]
Long term debt variable interest rate percentage	3.25%
Loan And Security Sixth Amendment Agreement [Member] \| Revolving Credit Facility [Member] \| Prime Rate [Member] \| Silicon Valley Bank [Member]
Debt Instrument [Line Items]
Debt instrument variable interest rate spread	2.50%
Debt instrument effective interest rate percentage	3.25%
Loan And Security Sixth Amendment Agreement [Member] \| Revolving Credit Facility [Member] \| Prime Rate [Member] \| Silicon Valley Bank [Member] \| Streamline Period
Debt Instrument [Line Items]
Debt instrument variable interest rate spread	1.50%