Future Minimum Payments Under Loans Payable (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
2020 (remaining 9 months)	$ 8,271
2021	7,254
Long-term Debt, Gross, Total	15,525
Less amount representing interest	(959)
Less unamortized discount	(290)	$ (400)
Less deferred charges	(790)
Less loans payable current, net of discount	(9,876)	(9,569)
Loans payable, net of current portion and discount	$ 3,610	$ 6,197

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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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Carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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