Cash and Credit Facilities - Narrative (Details)	12 Months Ended
Sep. 30, 2019 USD ($)
Interest Rate Swap
Line of Credit Facility [Line Items]
Notional amount of floating-to-fix interest rate swap	$ 36,000,000
Secured Debt \| Term loan
Line of Credit Facility [Line Items]
Secured term loan, face amount	70,000,000
Voluntary prepayment of line of credit	$ 12,700,000
Fixed charge coverage ratio	1.25
Ratio of debt to EBITDA	3.25
Secured Debt \| Term loan \| Maximum
Line of Credit Facility [Line Items]
Ratio of debt to EBITDA	4.25
Secured Debt \| Term loan \| Excess Cash Flow 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 adjusted EBITDA	75.00%
Ratio of funded indebtedness to adjusted EBIDTA	2.50
Secured Debt \| Term loan \| Excess Cash Flow Less Than 2.50 But Greater Than or Equal to 1.50
Line of Credit Facility [Line Items]
Percentage of excess cash flow for each year of funded indebtedness to adjusted EBITDA	50.00%
Secured Debt \| Term loan \| Excess Cash Flow Less Than 2.50 But Greater Than or Equal to 1.50 \| Maximum
Line of Credit Facility [Line Items]
Ratio of funded indebtedness to adjusted EBIDTA	2.50
Secured Debt \| Term loan \| Excess Cash Flow Equal to 1.50
Line of Credit Facility [Line Items]
Ratio of funded indebtedness to adjusted EBIDTA	1.5
Secured Debt \| Term loan \| Excess Cash Flow Less Than 1.50
Line of Credit Facility [Line Items]
Percentage of excess cash flow for each year of funded indebtedness to adjusted EBITDA	0.00%
Ratio of funded indebtedness to adjusted EBIDTA	1.5
Secured Debt \| Term loan \| LIBOR
Line of Credit Facility [Line Items]
Debt instrument, interest rate, effective percentage	2.10%
Secured Debt \| Term loan \| LIBOR \| Maximum
Line of Credit Facility [Line Items]
Debt instrument, interest rate, effective percentage	4.50%
Secured Debt \| Term loan \| LIBOR \| Minimum
Line of Credit Facility [Line Items]
Debt instrument, interest rate, effective percentage	2.50%
Secured Debt \| Revolving Line of Credit
Line of Credit Facility [Line Items]
Line of credit ceiling	$ 25,000,000
Remaining borrowing availability	16,300,000
Unused borrowing capacity	$ 16,300,000
Secured Debt \| Revolving Line of Credit \| LIBOR
Line of Credit Facility [Line Items]
Debt instrument, interest rate, effective percentage	2.10%
Secured Debt \| Letters of Credit
Line of Credit Facility [Line Items]
Remaining borrowing availability	$ 3,000,000

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Percentage of Excess Cash Flow For Each Year Of Funded Indebtedness to Adjusted EBITDA

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- Definition

Ratio of Debt to Earnings Before Interest, Taxes, Depreciations, and Amortization

+ References

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Ratio of Funded Indebtedness to Adjusted Earnings Before Interest, Taxes, Depreciations, and Amortization

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- Definition

Voluntary Repayments of Lines of Credit

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Face (par) amount of debt instrument at time of issuance.

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Amount of unused borrowing capacity under the long-term financing arrangement that is available to the entity as of the balance sheet date.

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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