Income Taxes - Summary of Effective Income Tax Rate Reconciliation (Detail)	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Income Tax Disclosure [Abstract]
At U.S. federal statutory rate	34.00%	34.00%
State taxes, net of federal effect	9.00%	9.30%
Stock compensation	(1.10%)	(0.70%)
Mark-to-market adjustments	(0.10%)	0.70%
Valuation allowance	(41.10%)	(43.40%)
Other	(0.70%)	0.10%
Effective income tax rate	0.00%	0.00%