Balance Sheet Components - Summary of Accrued and Other Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Accrued employee related costs	$ 3,420	$ 3,223
Accrued research and development costs	2,668	4,485
Accrued professional fees	817	357
Operating lease liability	187
Other	78	747
Total accrued and other liabilities	$ 7,170	$ 8,812

Accrued And Other Liabilities Current

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Accrued research and development costs current.

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Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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