Stock Compensation Plans (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jan. 27, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, outstanding, aggregate intrinsic value	$ 4,530	$ 8,030
Number of unvested stock options (shares)	155,750	183,150
Unvested stock options, aggregate grant date fair value	$ 485	$ 454
Unvested stock options, aggregate intrinsic value	$ 1,090
Stock options vested during period (shares)	37,300	43,900
Stock options vested during period, aggregate grant date fair value	$ 88	$ 104
Aggregate intrinsic value of options exercised during the period	751	$ 741
Unrecognized compensation expense, non-vested options	$ 401
Unrecognized compensation expense, non-vested options, amortization period (in years)	2 years 1 month 21 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	75,316
MRDP \| Stock Grant Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock grants awarded (shares)	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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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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).

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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.

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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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Number of shares authorized for issuance under share-based payment arrangement.

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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.

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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.

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

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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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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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