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Debt Instrument, Final Payment Accrual Charged To Interest Expense

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Debt [Line Items]

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Debt Prepayment Cost

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Line of credit facility termination fee percentage.

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Payment For Loan Facility Fees

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Prepayment Fee Percentage After Third Anniversary Of Loan Funding

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Prepayment Fee Percentage Before Second Anniversary Of Loan Funding

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Prepayment Fee Percentage Between Second And Third Anniversary Of Loan Funding

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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

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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.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Value of outstanding derivative securities that permit the holder the right to purchase securities (usually equity) from the issuer at a specified price.

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Debt - Additional information (Detail) - USD ($)			3 Months Ended		9 Months Ended
Debt - Additional information (Detail) - USD ($)	May 05, 2020	Feb. 28, 2019	Apr. 30, 2020	Apr. 30, 2019	Oct. 31, 2019	Jan. 31, 2020
Debt [Line Items]
Term loan			$ 20,000,000			$ 20,000,000
Amortization of debt discount			126,000	$ 108,000
Loss on extinguishment of debt			0	1,073,000
Loan facility fee payment			100,000	0
Amended And Restated Loan And Security Agreement
Debt [Line Items]
Debt instrument, fee percentage		2.75%
Final payment accrual charged to interest expense			257,000
Number of securities called by warrants		150,274
Exercise price (in dollars per share)		$ 8.02
Warrant liability		$ 833,000
Prepayment fee percentage before second anniversary of loan funding		3.00%
Prepayment fee percentage between second and third anniversary of loan funding		2.00%
Prepayment fee percentage after third anniversary of loan funding		1.00%
Interest expense			311,000
Amortization of debt discount			$ 39,000
Effective interest rate			6.20%
Term loan
Debt [Line Items]
Term loan		$ 20,000,000
Term loan \| Subsequent Event
Debt [Line Items]
Repayments of debt	$ 20,000,000
Prime Rate \| Amended And Restated Loan And Security Agreement \| Before EBITDA Benchmark
Debt [Line Items]
Interest rate		1.50%
Prime Rate \| Amended And Restated Loan And Security Agreement \| After EBITDA Benchmark
Debt [Line Items]
Interest rate		0.75%
Revolving Credit Facility \| Amended And Restated Loan And Security Agreement
Debt [Line Items]
Maximum borrowing capacity		$ 25,000,000	$ 25,000,000
Debt instrument, term					5 years
Debt instrument, fee percentage			0.15%
Interest expense			$ 36,000
Amortization of debt discount			$ 32,000
Borrowing base as a percentage of accounts receivable			80.00%
Line of credit, facility annual fee for first three years			$ 100,000
Loan facility fee payment			100,000
Line of credit, facility annual fee for fourth and fifth years			$ 75,000
Line of credit facility termination fee percentage			1.50%
Revolving Credit Facility \| Amended And Restated Loan And Security Agreement \| Before EBITDA Benchmark
Debt [Line Items]
Stated interest rate			5.00%
Revolving Credit Facility \| Amended And Restated Loan And Security Agreement \| After EBITDA Benchmark
Debt [Line Items]
Stated interest rate			4.75%
Revolving Credit Facility \| Second Amended And Restated Loan And Security Agreement \| Subsequent Event
Debt [Line Items]
Maximum borrowing capacity	$ 50,000,000
Stated interest rate	4.50%
Revolving Credit Facility \| Prime Rate \| Before EBITDA Benchmark
Debt [Line Items]
Interest rate			(0.50%)
Revolving Credit Facility \| Prime Rate \| After EBITDA Benchmark
Debt [Line Items]
Interest rate			(0.75%)
Term Loan B Advance
Debt [Line Items]
Debt instrument, term		36 months
Term Loan B Advance \| Amended And Restated Loan And Security Agreement
Debt [Line Items]
Maximum borrowing capacity		$ 10,000
Term Loan C Advance
Debt [Line Items]
Debt instrument, term		36 months
Term Loan C Advance \| Amended And Restated Loan And Security Agreement
Debt [Line Items]
Maximum borrowing capacity		$ 15,000,000
Loans Payable
Debt [Line Items]
Loss on extinguishment of debt				1,073,000
Write off of deferred debt issuance cost				773,000
Debt prepayment cost				300,000
Debt extinguishment and modification fee				$ 112,000