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Borrowings and Subordinated Notes - Additional Information (Detail) |  | 12 Months Ended |  |
--- | --- | --- | --- | ---
Jul. 30, 2021 USD ($) | Dec. 31, 2024 USD ($) Loan | Dec. 31, 2023 USD ($) | Mar. 31, 2023 USD ($) | Sep. 29, 2022 USD ($)
Debt Instrument [Line Items] |  |  |  |  |
Number of loans secured | Loan |  | 2 |  |  |
Term note |  | $ 30,000,000 |  |  |
Line of credit |  | 10,000,000 |  | $ 10,000,000 | $ 10,000,000
Variable line of credit |  | $ 15,000,000 |  |  |
Percentage of interest on loan accrued rate |  | 2.50% |  |  |
Percentage of line of credit accrues rate |  |  |  |  | 5.50%
Maturity date |  | Sep. 30, 2023 |  |  |
Total borrowings excluding for fair value related to acquisition |  | $ 246,095,000 | $ 265,800,000 |  |
Total borrowings, fair value related to acquisition |  | 39,000 | 23,000 |  |
Advances, secured by mortgage loans |  | 2,536,043,000 | 2,556,167,000 |  |
Unsecured borrowings through correspondent banks |  | 163,000,000 | 128,000,000.0 |  |
Borrowing capacity under the Federal Reserve's BTFP |  |  | 69,900,000 |  |
Borrowings capacity under federal reserve bank discount window |  | 29,900,000 |  |  |
Unpledged securities which could be sold or used as collateral |  | 170,400,000 | 97,300,000 |  |
Additional borrowings available from the Federal Home Loan Bank based on current pledging |  | $ 159,500,000 | 42,500,000 |  |
Debt instrument basis points | 2.63% |  |  |  |
Debt instrument, frequency of periodic payment | semi-annually |  |  |  |
Term of loan | 5 years |  |  |  |
Redemption price of principal amount of notes redeemed | 100.00% |  |  |  |
Prime Rate [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Maturity date |  | Sep. 27, 2025 |  |  |
Private Placement |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Subordinated notes | $ 35,000,000 |  |  |  |
Fixed-to-floating interest rate | 3.25% |  |  |  |
Subordinated notes, due date | Jul. 30, 2031 |  |  |  |
Percentage of notes prices on principal amount | 100.00% |  |  |  |
Peoples Federal Savings and Loan Association [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Bank undertook amount |  | $ 965,000 |  |  |
Peoples Federal Savings and Loan Association [Member] | Minimum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Bank loan maturity year |  | 2022 |  |  |
Peoples Federal Savings and Loan Association [Member] | Maximum [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Bank loan maturity year |  | 2028 |  |  |
Perpetual Federal Savings Bank {Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Bank undertook amount |  | $ 6,000,000 |  |  |
Federal Home Loan Bank Advances [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Bank entered Bermudan Putable advance |  | $ 15,000,000 |  |  |
Term of debt |  | 10 years |  |  |
Fixed rate |  | 3.40% |  |  |
Collateral Pledged [Member] | Federal Home Loan Bank Advances [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Pledging of eligible commercial real estate loans |  | $ 369,500,000 | 158,900,000 |  |
Asset Pledged as Collateral without Right [Member] | Federal Home Loan Bank Advances [Member] | 1-4 Family Real Estate Loans [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Advances, secured by mortgage loans |  | 202,000,000 |  |  |
Asset Pledged as Collateral without Right [Member] | Federal Home Loan Bank Advances [Member] | HALOC [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Advances, secured by mortgage loans |  |  | 232,000,000 |  |
Multi-family Real Estate Loans [Member] | Asset Pledged as Collateral without Right [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Advances, secured by mortgage loans |  | 47,700,000 |  |  |
Cash Management Advance |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Unsecured borrowings through correspondent banks |  | $ 163,700,000 | $ 150,100,000 |  |
Term Note [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Short term debt, term |  | 12-month |  |  |
Line of Credit [Member] |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |
Short term debt, term |  | 12-month |  |  |
Outstanding borrowings |  | $ 0 |  |  |

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- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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- Definition Maturity date of long-term debt, in YYYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)(a)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
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- Definition Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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- Definition Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(17)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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