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Statutory Capital and Surplus (Details) - USD ($) | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Statutory Accounting Practices [Line Items] |  |
Assets held-in-trust | $ 950,100,000 | $ 948,500,000
P&C Insurance and Reinsurance (Ark/WM Outrigger) | WM Outrigger Re - Segment |  |
Statutory Accounting Practices [Line Items] |  |
Statutory capital and surplus | 196,300,000 |
Minimum regulatory capital requirement | $ 1 |
P&C Insurance and Reinsurance (Ark/WM Outrigger) | Ark Insurance Holdings Limited - Segment |  |
Statutory Accounting Practices [Line Items] |  |
Percent of statutory capital balance | 15.00% |
Percent of statutory capital and surplus balance | 25.00% |
Maximum dividend payable | $ 336,700,000 |
Financial Guarantee (HG Global) | HG Global |  |
Statutory Accounting Practices [Line Items] |  |
Statutory capital and surplus | 718,300,000 |
Minimum regulatory capital requirement | 1 |
Net unrestricted cash | 6,500,000 |
Accrued interest | 157,500,000 |
Bamboo Captive |  |
Statutory Accounting Practices [Line Items] |  |
Statutory capital and surplus | 6,800,000 |
Minimum regulatory capital requirement | 500,000 |
Net unrestricted cash and short-term investments | 11,400,000 |
Ark |  |
Statutory Accounting Practices [Line Items] |  |
Funds provided | 361,500,000 |
Statutory capital and surplus | 1,346,700,000 |
Minimum regulatory capital requirement | $ 577,700,000 |

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- Definition Amount of the reinsurer's funds held on its behalf by the ceding insurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(10)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + Details
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- Definition Sum of investments and unrestricted cash as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478777/944-210-S99-1 + 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/2009/role/commonPracticeRef -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 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/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 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 944 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477908/944-505-50-1 + Details
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