Future Minimum Payments Under Loans Payable (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
2021 (remaining nine months)	$ 3,316
2022	11,785
2023	30,097
Long-term Debt, Gross, Total	45,198
Less amount representing interest	(6,976)
Less unamortized discount	(2,563)
Less deferred charges	(3,222)
Less loans payable current, net of discount		$ (1,056)
Loans payable, net of current portion and discount	$ 32,437	$ 12,716

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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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Amount, after accumulated amortization, of debt discount.

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The total amount of long-term liability charges that are being deferred beyond one year.

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Amount of interest payable on debt, including, but not limited to, trade payables.

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