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Earnings Per Share - Additional Information (Detail) | Jun. 03, 2022 USD ($) Director shares | Jun. 04, 2021 USD ($) Director shares | Oct. 01, 2021 USD ($) shares | Nov. 20, 2020 shares | Jun. 05, 2020 USD ($) shares
--- | --- | --- | --- | --- | ---
Earnings Per Share Basic [Line Items] |  |  |  |  |
Compensation annual basis committee award | $ | $ 10,013 | $ 6,000 |  |  | $ 4,000
Number of directors received shares | shares | 240 | 272 |  | 20 | 176
Number of directors received shares | Director | 12 | 10 |  |  |
Number of directors received prorated dollar value of shares | Director |  | 4 |  |  |
Perpetual Federal Savings Bank {Member] |  |  |  |  |
Earnings Per Share Basic [Line Items] |  |  |  |  |
Compensation annual basis committee award | $ |  |  | $ 1,523 |  |
Number of directors received shares | shares |  |  | 68 |  |

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