Fair Value of Financial Instruments (Details) - Company’s financial liabilities measured at fair value - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Convertible promissory notes embedded derivative liability [Member]
Recurring Financial Liabilities:
Financial Liability
Convertible promissory notes embedded derivative liability [Member] | Fair Value, Inputs, Level 1 [Member]
Recurring Financial Liabilities:
Financial Liability
Convertible promissory notes embedded derivative liability [Member] | Fair Value, Inputs, Level 2 [Member]
Recurring Financial Liabilities:
Financial Liability
Convertible promissory notes embedded derivative liability [Member] | Fair Value, Inputs, Level 3 [Member]
Recurring Financial Liabilities:
Financial Liability
Convertible preferred stock warrant liability [Member]
Recurring Financial Liabilities:
Financial Liability		67
Convertible preferred stock warrant liability [Member] | Fair Value, Inputs, Level 1 [Member]
Recurring Financial Liabilities:
Financial Liability
Convertible preferred stock warrant liability [Member] | Fair Value, Inputs, Level 2 [Member]
Recurring Financial Liabilities:
Financial Liability
Convertible preferred stock warrant liability [Member] | Fair Value, Inputs, Level 3 [Member]
Recurring Financial Liabilities:
Financial Liability		$ 67