Disclosures about Fair Value of Assets and Liabilities - (Losses)/Recoveries Recognized on Assets Measured on Non-Recurring Basis (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Non-recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans (collateral-dependent)	$ (68)	$ 7	$ (68)	$ 14

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.

No definition available.

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