Subsequent Events - Additional Information (Detail) - USD ($) $ in Millions		1 Months Ended
	Nov. 03, 2017	Jun. 30, 2016	Jun. 30, 2015
Subsequent Event [Line Items]
Stock Issued During Period Shares New Issues		5,882,352
Proceeds from Issuance Initial Public Offering		$ 9.3
Warrant [Member]
Subsequent Event [Line Items]
Stock Issued During Period Shares New Issues		2,941,176
Stock Issued During Period, Value, New Issues		$ 10.0	$ 25.0
Subsequent Event [Member] | Registered Direct Offering 2017 [Member]
Subsequent Event [Line Items]
Stock Issued During Period Shares New Issues	13,333,332
Stock Issued During Period, Value, New Issues	$ 4.0
Proceeds from Issuance Initial Public Offering	$ 3.6
Subsequent Event [Member] | Registered Direct Offering 2017 [Member] | Warrant [Member]
Subsequent Event [Line Items]
Stock Issued During Period Shares New Issues	6,666,666
Subsequent Event [Member] | Registered Direct Offering 2017 [Member] | Roth Capital Partners, Llc [Member] | Warrant [Member]
Subsequent Event [Line Items]
Stock Issued During Period Shares New Issues	160,000