Accrued Liabilities - Schedule of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Sep. 30, 2017
Accrued Liabilities Current [Abstract]
Accrued professional fees	$ 362	$ 501
Accrued clinical study expense	1,424	411
Accrued inventory purchases	692	596
Construction in progress	198
Customer claim	1,000
Other	346	265
Total	$ 4,022	$ 1,773