Balance Sheet Components - Components of Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Payroll-related expenses	$ 437	$ 398
Engineering services	221	134
Professional fees	95	48
Accrued warranty	77	73
Taxes payable	35	28
Other	25	37
Total accrued liabilities	$ 890	$ 718

Accrued engineering services current.

No definition available.

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- Definition

Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all currently due domestic and foreign income tax obligations.

+ References

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- Definition

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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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for statutory payroll taxes incurred through that date and withheld from employees pertaining to services received from them, including entity's matching share of the employees FICA taxes and contributions to the state and federal unemployment insurance programs. 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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- Definition

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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No definition available.

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- Definition

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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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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