Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

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The amount of plan compensation cost recognized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 40
-Section 50
-Paragraph 1
-Subparagraph (c)
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
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- Definition

The noncash expense that accounts for the value of stock or unit options distributed to employees as compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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Stock Based Compensation Plans (Additional Information) (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	19,440		19,440
Stock or Unit Option Plan Expense	$ 16,000		$ 39,000
Employee Stock Ownership Plan (Esop), Compensation Expense				$ 628,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			$ 0
Equity Incentive Plan 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	88,000		88,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value			$ 100,000
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value			$ 860,000
Employee Stock Option [Member] \| Equity Incentive Plan 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	66,000		66,000
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	4,735		4,735
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options	$ 606,000		$ 606,000
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period			4 years 4 months 20 days
Employee Stock Ownership Plan (Esop), Compensation Expense	$ 35,000	$ 0	$ 87,000	$ 0
Restricted Stock [Member] \| Equity Incentive Plan 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	22,000		22,000
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant	14,705		14,705
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options	$ 275,000		$ 275,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition			4 years 4 months 20 days