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Statement of Accounting Policies - Additional Information (Detail) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2022 USD ($) county Segment | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Summary Of Significant Accounting Policies [Line Items] |  |  |
Number of counties in which entity provides services | county | 26 |  |
Business segments | Segment | 1 |  |
Equity investments | 20.00% |  |
Loans past due days | 90 days |  |
Excess impaired credits | $ 250,000 |  |
Software purchases and developed are capitalized and amortized on straight-line basis | 7 years |  |
Cumulative Effect Of New Accounting Principle In Period Of Adoption |  |  | $ 11,199,000
Retained Earnings [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Cumulative Effect Of New Accounting Principle In Period Of Adoption |  |  | $ 11,199,000
Guaranteed Minimum Death Benefit [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Other liabilities | $ 3,700,000 | $ 4,500,000 |

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- Definition Amount, before effect of reinsurance, of present value of future benefit to be paid to or on behalf of policyholder and related expense less present value of future net premium receivable under insurance contract. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 55 -Paragraph 29E -URI https://asc.fasb.org/extlink&oid=126561865&loc=SL117819541-158441 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(13)(a)(1)) -URI https://asc.fasb.org/extlink&oid=126734703&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 65 -Paragraph 2 -Subparagraph (g)(1) -URI https://asc.fasb.org/extlink&oid=124501264&loc=SL117420844-207641 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 6 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=124506351&loc=d3e14931-158439 + Details
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