Additional Balance Sheet Information - Schedule of Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Disclosure Text Block Supplement [Abstract]
Research and development services	$ 1,970	$ 2,543
Employee compensation	1,073	1,761
Legal and professional fees	687	515
Accrued other	94	466
Accrued Liabilities	$ 3,824	$ 5,285

Accrued Research And Development Current

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- Definition

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).

+ References

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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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).

+ References

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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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