Income Taxes - Schedule of Effective Income Tax Rate Reconciliation (Detail) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income before income taxes	$ 15,187	$ 14,805
Federal income tax rate	21.00%	21.00%
Federal income tax expense at statutory rate	$ 3,189	$ 3,109
(Reduction) increases in income taxes resulting from: Tax exempt interest	(144)	(149)
(Reduction) increases in income taxes resulting from: State tax, net of federal tax effect	1,241	1,205
(Reduction) increases in income taxes resulting from: Incentive stock option compensation expense	17	28
(Reduction) increases in income taxes resulting from: Income from bank-owned life insurance	(333)	(289)
(Reductions) increases in income taxes resulting from: Other items, net	(153)	652
(Reductions) increases in income taxes resulting from: Impact of deferred tax rate adjustment		(897)
Total income tax expense	$ 3,817	$ 3,659
Effective income tax rate	25.13%	24.71%

Income tax reconciliation income from bank owned life insurance.

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of current and deferred federal income tax expense (benefit) attributable to income (loss) from continuing operations.

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Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income (loss) exempt from income taxes.

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