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Borrowings and Subordinated Notes - Additional Information (Detail) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Jul. 30, 2021 USD ($) | Dec. 31, 2021 USD ($) Loan | Dec. 31, 2020 USD ($)
Debt Instrument [Line Items] |  |  |
Number of loans secured | Loan |  | 2 |
Term note |  | $ 30,000 |
Line of credit |  | $ 10,000 |
Percentage of interest on loan accrues rate |  | 2.50% |
Total borrowings excluding for fair value related to acquisition |  | $ 23,868 | $ 18,000
Total borrowings, fair value related to acquisition |  | 197 | 164
Unsecured borrowings through correspondent banks |  | 69,000 | 69,000
Unpledged securities which could be sold or used as collateral |  | 313,600 | 206,700
Additional borrowings available from the Federal Home Loan Bank based on current pledging |  | $ 91,200 | 7,400
Debt instrument basis points | 2.63% |  |
Debt instrument, frequency of periodic payment | semi-annually |  |
Term of loan | 5 years | 3 years |
Redemption price of principal amount of notes redeemed | 100.00% |  |
Private Placement |  |  |
Debt Instrument [Line Items] |  |  |
Subordinated notes | $ 35,000 |  |
Fixed-to-floating interest rate | 3.25% |  |
Subordinated notes, due date | Jul. 30, 2031 |  |
Percentage of notes prices on principal amount | 100.00% |  |
Perpetual Federal Savings Bank {Member] |  |  |
Debt Instrument [Line Items] |  |  |
Bank undertook amount |  | $ 6,000 |
Mortgage Loans at Cost [Member] |  |  |
Debt Instrument [Line Items] |  |  |
Advances, secured by mortgage loans |  | 193,200 | 38,000
Cash Management Advance |  |  |
Debt Instrument [Line Items] |  |  |
Unsecured borrowings through correspondent banks |  | $ 94,200 | $ 79,100
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 |

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- Definition Federal Home Loan Bank advances general debt obligations disclosures amount of available unused funds based on current pledging. + References No definition available. + Details
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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 -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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