Balance Sheet Components - Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Construction-in-progress obligations	$ 3,422	$ 395
Contract manufacturing	250	834
Professional service fees	206	112
Pre-clinical and clinical studies	43	483
Accrued taxes	27	187
Other	206	403
Total	$ 4,154	$ 2,414

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.

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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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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are due within one year or operating cycle, if longer, from the balance sheet date.

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Accrued Construction-In-Progress Obligations, Current

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Accrued Contract Manufacturing, Current

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Accrued Pre-clinical and Clinical Study, Current

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Accrued Taxes, Current

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