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Leases - Additional Information (Detail) - USD ($) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Lessee Lease Description [Line Items] |  |  |  |
Lease expiration month and year |  |  | 2027-08 |
Future lease payments | $ 170,000 |  | $ 170,000 |
Operating lease expense | $ 9,000 | $ 8,000 | $ 18,000 | $ 16,000
Branch Office and Certain Equipment [Member] |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |
Operating leases expiration beginning year |  |  | 2024 |
Operating leases expiration ending year |  |  | 2027 |
Operating lease option to extend |  |  | true |
Operating lease, renewal term | 4 years |  | 4 years |

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- Definition Lessee operating lease expiration beginning year. + References No definition available. + Details
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- Definition Lessee operating lease expiration ending year. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147478964/842-20-50-3 + Details
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- Definition Indicates (true false) whether lessee has option to extend operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147478964/842-20-50-3 + Details
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- Definition Term of lessee's operating lease renewal, 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 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147478964/842-20-50-3 + Details
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- Definition Amount of operating lease expense. Excludes sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479041/842-20-45-4 + Details
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- Definition Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 840 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 40 -Subparagraph (Note 3) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481418/840-10-55-40 Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Topic 840 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481501/840-20-50-2 + Details
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- Details
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