Securities Available for Sale - Sales of Securities Available for Sale (Detail) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Investments Debt And Equity Securities [Abstract]
Proceeds from sales of securities	$ 75,401	$ 254,606	$ 83,008
Gross realized gains	190		1,270
Gross realized losses	(513)	(31)	(1,660)
Net loss on sales of securities	$ (323)	$ (31)	$ (390)

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 50
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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
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-Publisher FASB
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