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Statutory Information - Summary of Amounts Disclosed Under Statutory Accounting Practices (Details) - USD ($) $ in Thousands | 3 Months Ended |
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Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025
Statutory Capital [Abstract] |  |  |
Statutory net income | $ 144,899 | $ 172,182 |
Statutory policyholders' surplus | 1,034,546 |  | $ 894,278
Contingency loss reserves | $ 4,942,209 |  | $ 4,914,234

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- Definition An amount of money established from retained earnings to allow for unforeseen losses in business. Amount of reserves for future policy claims payable and loss expenses to be incurred. + References No definition available. + Details
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- References No definition available. + Details
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- Definition The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 505 -Name Accounting Standards Codification -Section 55 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478420/944-505-55-2 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 505 -Name Accounting Standards Codification -Section 55 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147478420/944-505-55-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 505 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477908/944-505-50-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(c)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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- Definition Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(23)(c)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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