Securities - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2020
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	$ 154,486		$ 155,588
Fair Value	$ 161,292		162,394
Percentage of equity securities	10.00%
Carrying value of securities pledged as collateral	$ 73,908		66,186
Repurchase agreements	4,383		3,738
Gross gains from sales of available for sale securities	204	$ 1
Gross losses from sales of available for sale securities	0	0
Tax benefit to net realized gains (losses)	58	$ 0
Investments in debt and marketable equity securities	$ 27,195		$ 24,574
Temporarily impaired debt securities percentage of investment securities portfolio	17.00%		16.00%
Maturity Overnight [Member]
Debt Securities, Available-for-sale [Line Items]
Repurchase agreements	$ 2,700
Maturity 30 to 90 Days [Member]
Debt Securities, Available-for-sale [Line Items]
Repurchase agreements	1,700
Mortgage-backed Securities - GSE Residential [Member]
Debt Securities, Available-for-sale [Line Items]
Mortgage-backed securities with a book value	142,008		$ 143,033
Fair Value	147,954		148,855
Investments in debt and marketable equity securities	27,134		24,513
Debt Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Investments in debt and marketable equity securities	$ 27,195		$ 24,574

Debt securities greater than stated percentage of equity securities.

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Temporarily impaired debt securities percentage of investment securities portfolio.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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The sum of the fair values, as of the date of each statement of financial position presented, of securities that are restricted as collateral for the payment of related debt obligations, primarily secured borrowings and repurchase agreements, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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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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Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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