Employee stock ownership plan ESOP debt structure employer loan expected loan repayment period.

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- Definition

Employee stock ownership plan ESOP minimum age.

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Employee stock ownership plan ESOP percentage of shares purchased.

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- Definition

Employee stock ownership plan ESOP period of service to qualify for employee stock ownership plan.

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- Definition

Share based compensation arrangement by share based payment award prorated vesting period.

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No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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- Definition

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 nonvested award under share-based payment arrangement. Excludes share and unit options.

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- Definition

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

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

This item represents the number of shares provided to the Employee Stock Ownership Plan (ESOP) during the period.

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- Definition

Sum of the allocated, committed-to-be-released and suspense shares of the entity held by the plan.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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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No definition available.

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

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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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Net number of share options (or share units) granted during the period.

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Percentage of vesting of award under share-based payment arrangement.

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Number of options vested.

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No definition available.

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Stock-based Compensation - Additional Information (Detail) - USD ($)		3 Months Ended		6 Months Ended
	Dec. 10, 2013	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2016	Jun. 30, 2020	Dec. 10, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares paid under ESOP		358,042			358,042
Employee Stock Ownership Plan Esop [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Minimum hours of service required		1000 hours
Period of service to qualify for ESOP benefits		12 months
Minimum age of employee to attain the plan		0 years
Shares to be purchased for ESOP, from borrowed funds		384,900
Shares to be purchased for ESOP, percentage of common stock		8.00%
Repayment of loan on ESOP		20 years
Percentage vested in accrued benefits		100.00%
Vesting period		6 years
Employee Stock Ownership Plan Esop [Member] \| Employee Severance [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares paid under ESOP		0	0
Employee Stock Ownership Plan Esop [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Prorated vesting period		2 years
Employee Stock Ownership Plan Esop [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Prorated vesting period		5 years
Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized		673,575
Equity Incentive Plan [Member] \| Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	7 years
Shares authorized	167,000	481,125
Restricted stock available for future grants		314,125
Stock options granted		0
Options vested during the period		0	0
Total unrecognized compensation cost related to non-vested stock options		$ 9,000
Weighted average recognition period for non-vested restricted stock awards		2 months 12 days
Stock based compensation expense		$ 42,000	$ 42,000
Tax benefit		$ 12,000	$ 12,000
Equity Incentive Plan [Member] \| Restricted Stock And Restricted Stock Units Rsu [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized		192,450
Equity Incentive Plan [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	10 years			8 years
Shares authorized	85,500					16,900
Restricted stock available for future grants		90,050
Weighted average recognition period for non-vested restricted stock awards		3 years 2 months 12 days
Unrecognized compensation expense for non-vested restricted stock awards		$ 536,000