Common Stock, Common Stock Warrants and Stock Option Plan - Common Stock Warrants - Additional Information (Details) - Common Stock Warrants [Member]	12 Months Ended
Dec. 31, 2017 shares
Class Of Warrant Or Right [Line Items]
Warrants expired (in shares)	7,378
Warrants exercised (in shares)	14,713
Shares issued upon exercising warrants (in shares)	10,223

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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