Fair Value Measurements - Fair value of Assets Measured on a Recurring Basis and Nonrecurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021
Nonrecurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreclosed and repossessed assets held for sale	$ 144	$ 280
Fair Value, Inputs, Level 3 | Nonrecurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Foreclosed and repossessed assets held for sale	144	280
US States and Political Subdivisions Debt Securities | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	46,869	47,696
US States and Political Subdivisions Debt Securities | Fair Value, Inputs, Level 1 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
US States and Political Subdivisions Debt Securities | Fair Value, Inputs, Level 2 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	46,869	47,696
US States and Political Subdivisions Debt Securities | Fair Value, Inputs, Level 3 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Corporate Obligations | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	18,832	20,311
Corporate Obligations | Fair Value, Inputs, Level 1 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Corporate Obligations | Fair Value, Inputs, Level 2 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	18,832	20,311
Corporate Obligations | Fair Value, Inputs, Level 3 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Other Debt Obligations | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	608	672
Other Debt Obligations | Fair Value, Inputs, Level 1 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Other Debt Obligations | Fair Value, Inputs, Level 2 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	608	672
Other Debt Obligations | Fair Value, Inputs, Level 3 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Total MBS and CMOs | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	143,100	138,341
Total MBS and CMOs | Fair Value, Inputs, Level 1 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	0	0
Total MBS and CMOs | Fair Value, Inputs, Level 2 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	143,100	138,341
Total MBS and CMOs | Fair Value, Inputs, Level 3 | Recurring Measurements
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Available-for-sale Securities	$ 0	$ 0