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Income Taxes - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2018
Income Taxes [Line Items] |  |  |  |
Securities transactions income tax (benefit) expense | $ 453,000 | $ 220,000 | $ (82,000) |
Federal tax rate, percentage | 21.00% | 21.00% | 21.00% |
Recognition of interest and penalties related to unrecognized tax benefits | $ 0 | $ 0 | $ 0 |
Amended Open tax | 2023 |  |  |
Earliest Tax Year [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Year under examination | 2019 |  |  | 2018
Latest Tax Year [Member] |  |  |  |
Income Taxes [Line Items] |  |  |  |
Year under examination | 2021 |  |  |

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- Definition Income taxes. + References No definition available. + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.Fact.4) -URI https://asc.fasb.org/extlink&oid=122134291&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(2)) -URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 + Details
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- Definition Tax year that remains open to examination under enacted tax laws, in YYYY format. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (e) -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319 + Details
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- Definition Amount of expense for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32718-109319 + Details
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