Disclosures about Fair Value of Assets - Fair Value Measurement of Assets Recognized on Nonrecurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2018	Jun. 30, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans (collateral dependent)	$ 9,342	$ 11,595
Non-recurring [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans (collateral dependent)		6,287
Non-recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Impaired loans (collateral dependent)		$ 6,287