Balance Sheet Components - Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Construction-in-progress obligations	$ 2,055	$ 395
Pre-clinical and clinical study	891	483
Professional service fees	306	112
Contract manufacturing	158	834
Accrued taxes	20	187
Other	248	408
Total	$ 3,678	$ 2,419

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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