Fair Value Measurements - Assets and Liabilities Carried at Fair Value Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Jun. 30, 2017
Assets:
Cash equivalents	$ 6,800	$ 13,521
Total cash equivalents	6,800	13,521
Liabilities:
Derivative liabilities	6,957
Total derivative liabilities	6,957
Quoted Prices in Active Markets (Level 1) [Member]
Assets:
Cash equivalents	6,800	13,521
Total cash equivalents	6,800	13,521
Liabilities:
Derivative liabilities	0
Total derivative liabilities	0
Significant Other Observable Inputs (Level 2) [Member]
Assets:
Cash equivalents	0	0
Total cash equivalents	0	0
Liabilities:
Derivative liabilities	0
Total derivative liabilities	0
Significant Unobservable Inputs (Level 3) [Member]
Assets:
Cash equivalents	0	0
Total cash equivalents	0	0
Liabilities:
Derivative liabilities	6,957	$ 0
Total derivative liabilities	$ 6,957