Fair Value of Financial Instruments - Summary of Assets and Liabilities Measured at Fair Value (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Jun. 30, 2019
Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	$ 52,636	$ 73,567
Total liabilities at fair value	6,644	1,339
Measured on a Recurring Basis [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	19,089	36,911
Measured on a Recurring Basis [Member] | Corporate and Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	5,026	8,360
Measured on a Recurring Basis [Member] | Mortgage-backed Securities - Residential [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	21,877	26,957
Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	425	1,417
Impaired Loans [Member] | Residential Mortgages [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	316	616
Impaired Loans [Member] | Commercial Loans [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	101	141
Impaired Loans [Member] | Home Equity Lines Of Credit [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	8	7
Foreclosed Real Estate [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value		653
Derivatives – Interest Rate Contracts [Member] | Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	6,644	1,339
Total liabilities at fair value	6,644	1,339
Level 2 [Member] | Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	52,636	73,567
Total liabilities at fair value	6,644	1,339
Level 2 [Member] | Measured on a Recurring Basis [Member] | U.S. Government and Agency Obligations [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	19,089	36,911
Level 2 [Member] | Measured on a Recurring Basis [Member] | Corporate and Other Debt Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	5,026	8,360
Level 2 [Member] | Measured on a Recurring Basis [Member] | Mortgage-backed Securities - Residential [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	21,877	26,957
Level 2 [Member] | Derivatives – Interest Rate Contracts [Member] | Measured on a Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	6,644	1,339
Total liabilities at fair value	6,644	1,339
Level 3 [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	425	1,417
Level 3 [Member] | Impaired Loans [Member] | Residential Mortgages [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	316	616
Level 3 [Member] | Impaired Loans [Member] | Commercial Loans [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	101	141
Level 3 [Member] | Impaired Loans [Member] | Home Equity Lines Of Credit [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value	$ 8	7
Level 3 [Member] | Foreclosed Real Estate [Member] | Measured on a Non-Recurring Basis [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets at fair value		$ 653