Employee Benefits - Significant Balances, Costs and Assumptions (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Retirement Benefits [Abstract]
Benefit obligation	$ 3,306	$ 2,919	$ 2,770
Fair value of plan assets
Funded status	(3,306)	(2,919)
Accumulated benefit obligation	3,306	2,919
Amounts recognized in the consolidated balance sheets:
Accrued benefit cost	$ 3,306	$ 2,919

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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Amount of funded (unfunded) status of defined benefit plan, measured as difference between fair value of plan assets and benefit obligation. Includes, but is not limited to, overfunded (underfunded) status.

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Amount of liability, recognized in statement of financial position, for defined benefit other postretirement plan. Excludes pension plan.

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