XML 49 R38.htm IDEA: XBRL DOCUMENT v3.8.0.1
Stock-Based Compensation - Assumptions Used to Value Stock Options (Detail) - $ / shares
3 Months Ended
Dec. 31, 2017
Dec. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions And Methodology [Abstract]    
Risk-free interest rate, minimum 2.05% 1.34%
Risk-free interest rate, maximum 2.22% 1.44%
Volatility 110.00% 79.00%
Expected life (in years) 6 years 3 months 6 years 3 months
Weighted average grant date fair value per share of options granted $ 3.03 $ 4.49