Credit Facilities - Narrative (Details)	3 Months Ended
Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)
Line of Credit Facility [Line Items]
Debt amortization fiscal year 2021	$ 14,400,000
Debt amortization fiscal year 2022	7,000,000
2023	8,750,000
2024	8,750,000
Debt amortization 2025	38,500,000
Interest Rate Swap
Line of Credit Facility [Line Items]
Derivative notional amount	$ 28,800,000	$ 36,000,000
Derivative fixed interest rate	1.61%
Interest expense increase (less than)	$ 200,000
Secured Debt \| Term Loans
Line of Credit Facility [Line Items]
Fixed charge coverage ratio	1.25
Ratio of funded indebtedness to EBITDA through maturity	2.75
Debt amortization fiscal year 2021	$ 7,000,000.0
Debt amortization fiscal year 2022	7,000,000.0
2023	8,750,000
2024	8,750,000
Debt amortization 2025	$ 8,750,000
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
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	3.75
Interest rate spread	4.50%
Secured Debt \| Term Loans \| Maximum \| Excess Cash Flows Less Than 2.50
Line of Credit Facility [Line Items]
Ratio of funded indebtedness to adjusted EBDTA, actual	2.50
Secured Debt \| Term Loans \| Minimum
Line of Credit Facility [Line Items]
Interest rate spread	2.50%
Secured Debt \| Term Loans \| LIBOR
Line of Credit Facility [Line Items]
Interest rate spread	0.15%
Secured Debt \| Revolving Line of Credit
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity	$ 25,000,000.0
Line of credit outstanding balance	9,200,000
Line of credit, current borrowing capacity	$ 25,000,000.0
Secured Debt \| Revolving Line of Credit \| LIBOR
Line of Credit Facility [Line Items]
Interest rate spread	0.15%
Secured Debt \| Letter of Credit
Line of Credit Facility [Line Items]
Line of credit, current borrowing capacity	$ 5,000,000

Fixed Charge Coverage Ratio

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Interest Expense Increase (Decrease)

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- Definition

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

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

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

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Fixed interest rate related to the interest rate derivative.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

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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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in remainder of current fiscal year.

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