Basis of Presentation and Significant Accounting Policies - Summary of Changes in Level 3 Fair Value Measurements (Details) - Level 3 - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
	Dec. 14, 2015	Mar. 31, 2019	Mar. 31, 2019
PFG V Debt, Net of Discount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of September 30, 2018			$ 1,905
Disbursement	$ 2,300
Payments			(333)
Amortization and accretion expense			51
Balance as of March 31, 2019		$ 2,094	2,094
Warrant Debt, PFG V
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of September 30, 2018			103
Payments			0
Amortization and accretion expense		5	9
Balance as of March 31, 2019		138	138
Burish Notes, Net of Discount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of September 30, 2018			0
Payments			0
Amortization and accretion expense			13
Balance as of March 31, 2019		$ 3,339	3,339
Disbursement of Tranche 2, net of discount | PFG V Debt, Net of Discount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			471
Disbursement of Tranche 2, net of discount | Warrant Debt, PFG V
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			26
Disbursement of Tranche 2, net of discount | Burish Notes, Net of Discount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			0
Disbursement of Tranches 1-4 | PFG V Debt, Net of Discount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			0
Disbursement of Tranches 1-4 | Warrant Debt, PFG V
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			0
Disbursement of Tranches 1-4 | Burish Notes, Net of Discount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			4,000
Warrant | PFG V Debt, Net of Discount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			0
Warrant | Warrant Debt, PFG V
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			0
Warrant | Burish Notes, Net of Discount
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Disbursement			$ 674