Cash and Credit Facilities - Summary of Loan Facilities and Subordinated Debt Financing (Details) - Secured Debt - USD ($)	12 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Total bank debt obligation	$ 56,000,000	$ 7,708,000
Term loan
Debt Instrument [Line Items]
Secured term loan, face amount	70,000,000
Total bank debt obligation	$ 56,000,000
Term loan \| LIBOR
Debt Instrument [Line Items]
Debt instrument, interest rate, effective percentage	2.10%
Debt instrument, basis spread on variable rate	4.00%
Revolving Line of Credit
Debt Instrument [Line Items]
Secured revolving line of credit, ceiling	$ 25,000,000
Total bank debt obligation	$ 0
Revolving Line of Credit \| LIBOR
Debt Instrument [Line Items]
Debt instrument, interest rate, effective percentage	2.10%
Debt instrument, basis spread on variable rate	4.00%

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

No definition available.

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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

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-Publisher FASB
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-Section S99
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

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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

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-Publisher FASB
-Name Accounting Standards Codification
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