Stock Compensation Plans (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Jan. 27, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, outstanding, aggregate intrinsic value	$ 5,790	$ 4,120
Number of unvested stock options (shares)	198,050	216,750
Unvested stock options, aggregate grant date fair value	$ 484	$ 424
Unvested stock options, aggregate intrinsic value	$ 2,620
Stock options vested during period (shares)	29,500	33,700
Stock options vested during period, aggregate grant date fair value	$ 75	$ 82
Aggregate intrinsic value of options exercised during the period	613	$ 413
Unrecognized compensation expense, non-vested options	$ 404
Unrecognized compensation expense, non-vested options, amortization period (in years)	2 years 1 month 28 days
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized	300,000
Award vesting percentage	20.00%
Award vesting period (years)	5 years
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term	10 years
Number of unvested shares	0	0
Equity Incentive Plan 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized			352,366
Number of shares available for grant	116,866
MRDP \| Stock Grant Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	0	0

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Percentage

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Aggregate Grant Date Fair Value

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period

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Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Aggregate Intrinsic Value

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- Definition

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.

+ 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 (i)
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Unrecognized cost of unvested options awarded to employees as compensation.

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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.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Subparagraph (c)(2)(iii)(1)
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
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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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

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.

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- Definition

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.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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