Credit Facilities - Narrative (Details)	6 Months Ended
	Mar. 31, 2020 USD ($)	Sep. 30, 2019 USD ($)
Line of Credit Facility [Line Items]
Total bank debt obligation	$ 2,000,000
Interest Rate Swap
Line of Credit Facility [Line Items]
Derivative notional amount		$ 36,000,000
Derivative fixed interest rate		1.61%
Interest expense reduction (less than)	100,000
Secured Debt
Line of Credit Facility [Line Items]
Total bank debt obligation	53,000,000	$ 56,000,000
Secured Debt | Term Loans
Line of Credit Facility [Line Items]
Secured term loan, face amount	$ 70,000,000
Fixed charge coverage ratio	1.25
Ratio of funded indebtedness to EBITDA through maturity	3.25
Total bank debt obligation	$ 53,000,000
Secured Debt | Term Loans | Excess Cash Flows Greater Than Or Equal to 2.50
Line of Credit Facility [Line Items]
Percentage of excess cash flow for each year of funded indebtedness to EBDTA	75.00%
Ratio of funded indebtedness to adjusted EBDTA, actual	2.50
Secured Debt | Term Loans | Excess Cash Flows Less Than 2.50 But Greater Than 1.50 [Member]
Line of Credit Facility [Line Items]
Percentage of excess cash flow for each year of funded indebtedness to EBDTA	50.00%
Secured Debt | Term Loans | Excess Cash Flows Equal to 1.50
Line of Credit Facility [Line Items]
Ratio of funded indebtedness to adjusted EBDTA, actual	1.5
Secured Debt | Term Loans | Excess Cash Flows Less Than 1.50
Line of Credit Facility [Line Items]
Percentage of excess cash flow for each year of funded indebtedness to EBDTA	0.00%
Ratio of funded indebtedness to adjusted EBDTA, actual	1.5
Secured Debt | Term Loans | Maximum
Line of Credit Facility [Line Items]
Ratio of funded indebtedness to EBITDA through maturity	4.25
Secured Debt | Term Loans | Maximum | Excess Cash Flows Less Than 2.50 But Greater Than 1.50 [Member]
Line of Credit Facility [Line Items]
Ratio of funded indebtedness to adjusted EBDTA, actual	2.50
Secured Debt | Term Loans | LIBOR
Line of Credit Facility [Line Items]
Interest rate spread	0.99%
Secured Debt | Term Loans | LIBOR | Maximum
Line of Credit Facility [Line Items]
Interest rate spread	4.50%
Secured Debt | Term Loans | LIBOR | Minimum
Line of Credit Facility [Line Items]
Interest rate spread	2.50%
Secured Debt | Revolving Line of Credit
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 25,000,000
Total bank debt obligation	2,000,000
Line of credit, current borrowing capacity	$ 21,300,000
Secured Debt | Revolving Line of Credit | LIBOR
Line of Credit Facility [Line Items]
Interest rate spread	990.00%
Secured Debt | Letter of Credit
Line of Credit Facility [Line Items]
Line of credit, current borrowing capacity	$ 3,000,000