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Subordinated Debt (Details Textual) - Subordinated Debt - USD ($)			9 Months Ended
	Jun. 28, 2013	Jun. 28, 2013	Sep. 30, 2018	May 04, 2017	Oct. 20, 2015
2021 Debenture
Debt Instrument [Line Items]
Subordinated debenture, principal amount	$ 3,000,000	$ 3,000,000
Fixed annual interest rate (as a percent)	8.00%	8.00%
Subordinated debenture, maturity date		Jun. 28, 2021
Subordinated debenture, maturity date range, start	Jun. 28, 2016
Warrants issued to purchase common stock (in shares)	48,750
Common stock exercise price (in dollars per share)	$ 19.33
Number of shares withheld in accordance with warrant's cashless exercise feature (in shares)				32,835
Common stock, shares issued (in shares)				15,915
2025 Note
Debt Instrument [Line Items]
Subordinated debenture, principal amount					$ 10,000,000.0
Fixed annual interest rate (as a percent)					6.4375%
2026 Notes
Debt Instrument [Line Items]
Subordinated debenture, principal amount			$ 25,000,000.0
Fixed annual interest rate (as a percent)			6.00%
LIBOR | 2026 Notes
Debt Instrument [Line Items]
Basis spread on variable rate			485.00%

X

- Definition

Class Of Warrant Or Right, Number Of Securities Withheld For Cashless Exercise Feature

+ References

No definition available.

+ Details

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X

- Definition

Represents the exercise price of the common stock.

+ References

No definition available.

+ Details

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- Definition

Represents the issue of warrants to purchase common stock during the period.

+ References

No definition available.

+ Details

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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ 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(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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.

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X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ 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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Earliest date the outstanding debt instruments are required to be repaid, in CCYY-MM-DD format.

+ 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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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