Other Financial Information - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Other Financial Information [Abstract]
Insurance	$ 412	$ 256
Interest receivable	575	439
Supplier advances	197	124
Software license	260	193
Other prepaid expenses and current assets	885	330
Total prepaid and other current assets	$ 2,329	$ 1,342

Other Financial Information

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Prepaid Software (Term) License

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Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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Amount of consideration paid in advance for supplies that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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