Securities Held to Maturity - Stratification by Contractual Maturity of Securities (Detail) - Debt Securities [Member] - USD ($) $ in Thousands	Dec. 31, 2018	Jun. 30, 2018
Schedule Of Held To Maturity Securities [Line Items]
Due in one year or less, Amortized Cost	$ 7,416
Due after one year through five years, Amortized Cost	32,115
Due after five years through ten years, Amortized Cost	120,857
Due after ten years, Amortized Cost	3,693
Amortized Cost	164,081	$ 155,777
Due in one year or less, Fair Value	7,395
Due after one year through five years, Fair Value	31,769
Due after five years through ten years, Fair Value	119,491
Due after ten years, Fair Value	3,663
Held-to-maturity Securities, Fair Value Total	$ 162,318	$ 153,744

Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing in sixth through tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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Fair value of investment in debt security measured at amortized cost (held-to-maturity), with single maturity date and allocated without single maturity date, maturing after tenth fiscal year following latest fiscal year. Excludes interim and annual periods when interim period is reported on rolling approach, from latest statement of financial position date.

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