Cash and Credit Facilities - Summary of Loan Facilities and Subordinated Debt Financing (Details)	12 Months Ended
Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($)
Debt Instrument [Line Items]
Debt instrument, interest rate, effective percentage	1.24%
Fixed charge coverage ratio	0.0135
Ratio of debt to EBITDA, period one	0.0299
Ratio of debt to EBITDA, period two	3.25
Ratio of debt to EBITDA, period three	0.025
Bank term loan
Debt Instrument [Line Items]
Maximum availability	$ 25,000,000
Bank term loan \| Term Loan with Fifth Third Bank
Debt Instrument [Line Items]
Maximum availability	$ 25,000,000
Debt instrument, payment term for consecutive monthly installments	59 months
Line of credit facility, periodic payment, principal	$ 312,500,000
Bank term loan \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Bank revolving line of credit
Debt Instrument [Line Items]
Maximum availability	$ 10,000,000
Bank revolving line of credit \| LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.00%
Notes Payable to Banks
Debt Instrument [Line Items]
Bank term loan	$ 19,688,000
Notes Payable to Banks \| Bank term loan
Debt Instrument [Line Items]
Bank term loan	19,688,000	$ 23,438,000
Notes Payable to Banks \| Bank revolving line of credit
Debt Instrument [Line Items]
Bank term loan	$ 0

Debt Instrument, Payment Terms, Number of Equal Payments

No definition available.

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- Definition

Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

+ Details

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- Definition

Amount of the required periodic payment applied to principal.

+ References

+ Details

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- Details

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