Debt - Additional Information (Detail) $ in Millions	1 Months Ended	3 Months Ended
Dec. 31, 2018 USD ($) Installment	Mar. 31, 2019 USD ($)
SVB Term Loan
Debt Instrument [Line Items]
Total principal amout	$ 56.0
Debt maturity date	Dec. 01, 2023
Debt instrument interest rate percentage	6.30%
Frequency of periodic payment		monthly
Number of installments \| Installment	36
Number of installments if achieving trailing revenue target and company so elects \| Installment	30
Debt instrument description		Beginning on December 1, 2020 (or June 1, 2021, if the Company achieves a trailing twelve-month revenue of at least a specified amount and elects to apply such later date), the Company will make thirty-six equal monthly payments of principal (or thirty equal payments, if the Company so elects).
Final payment percentage of original principal amount	3.15%
Proceeds from term loan		$ 55.4
Legal and consulting fees		0.6
CRG Term Loan
Debt Instrument [Line Items]
Debt extinguishment loss		2.4
Write-off of unamortized debt discount and debt issuance costs		$ 0.3

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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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

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

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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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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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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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- Definition

Cash received from principal payments made on loans related to operating activities.

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- Definition

A fee charged for services from professionals such as doctors, lawyers and accountants. The term is often expanded to include other professions, for example, pharmacists charging to maintain a medicinal profile of a client or customer.

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

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Final payment percentage of original principal amount.

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Number of installments.

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Number of installments if achieving trailing revenue target and company so elects.

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