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SEGMENT REPORTING - Schedule of Gross Premiums Written by Line of Business (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 USD ($) segment | Mar. 31, 2024 USD ($) | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Segment Reporting Information |  |  |  |
Number of operating segments | segment | 2 |  |  |
Gross premiums written | $ 247,945 | $ 217,258 |  |
Net premiums written | 219,397 | 194,077 |  |
Net premiums earned | 168,463 | 161,536 |  |
Net loss and LAE incurred | (122,884) | (109,326) |  |
Acquisition costs | (46,866) | (41,610) |  |
Other underwriting expenses | (6,358) | (6,339) |  |
Deposit interest expense, net | (149) | (876) |  |
Underwriting income (loss) | (7,794) | 3,385 |  |
Net investment income | 8,287 | 13,178 |  |
Corporate and other expenses | (4,672) | (4,375) |  |
Income from investment in Solasglas | 32,197 | 18,248 |  |
Foreign exchange gains (losses) | 4,355 | (1,649) |  |
Interest expense | (1,464) | (1,249) |  |
Income before income tax | 30,909 | 27,538 |  |
Attritional losses | (91,651) | (91,488) |  |
CAT losses | (27,015) | (12,437) |  |
Prior year adverse (favorable) loss development | 4,218 | 5,401 | $ 4,218 | $ 5,401
Total net loss and LAE incurred | 122,884 | 109,326 |  |
Total allocated assets | 2,152,096 | 1,876,969 | 2,016,223 |
Operating Segments |  |  |  |
Segment Reporting Information |  |  |  |
Prior year adverse (favorable) loss development | 4,329 | 1,472 |  |
Corporate |  |  |  |
Segment Reporting Information |  |  |  |
Gross premiums written | (230) | 129 |  |
Net premiums written | (183) | 117 |  |
Net premiums earned | (183) | 9,729 |  |
Net loss and LAE incurred | 225 | (9,499) |  |
Acquisition costs | 48 | (1,978) |  |
Other underwriting expenses | 0 | 0 |  |
Deposit interest expense, net | 0 | 0 |  |
Underwriting income (loss) | 90 | (1,748) |  |
Net investment income | 2,068 | 745 |  |
Corporate and other expenses | (4,100) | (3,785) |  |
Income from investment in Solasglas | 32,197 | 18,248 |  |
Foreign exchange gains (losses) | 4,355 | (1,649) |  |
Interest expense | (1,464) | (1,249) |  |
Income before income tax | 33,146 | 10,562 |  |
Attritional losses | 114 | (5,570) |  |
CAT losses | 0 | 0 |  |
Prior year adverse (favorable) loss development | (111) | 3,929 | (111) | 3,929
Total net loss and LAE incurred | (225) | 9,499 |  |
Total allocated assets | 1,547,145 | 1,304,210 |  |
Open Market | Operating Segments |  |  |  |
Segment Reporting Information |  |  |  |
Gross premiums written | 220,709 | 187,061 |  |
Net premiums written | 195,609 | 167,716 |  |
Net premiums earned | 149,641 | 131,610 |  |
Net loss and LAE incurred | (112,763) | (86,700) |  |
Acquisition costs | (40,881) | (33,579) |  |
Other underwriting expenses | (4,797) | (5,478) |  |
Deposit interest expense, net | (149) | (876) |  |
Underwriting income (loss) | (8,949) | 4,977 |  |
Net investment income | 5,771 | 12,616 |  |
Corporate and other expenses | 0 | 0 |  |
Income before income tax | (3,178) | 17,593 |  |
Attritional losses | (80,852) | (72,790) |  |
CAT losses | (27,015) | (12,437) |  |
Prior year adverse (favorable) loss development | 4,896 | 1,473 | 4,896 | 1,473
Total net loss and LAE incurred | 112,763 | 86,700 |  |
Total allocated assets | 459,549 | 479,820 |  |
Innovations | Operating Segments |  |  |  |
Segment Reporting Information |  |  |  |
Gross premiums written | 27,466 | 30,068 |  |
Net premiums written | 23,971 | 26,244 |  |
Net premiums earned | 19,005 | 20,197 |  |
Net loss and LAE incurred | (10,346) | (13,127) |  |
Acquisition costs | (6,033) | (6,053) |  |
Other underwriting expenses | (1,561) | (861) |  |
Deposit interest expense, net | 0 | 0 |  |
Underwriting income (loss) | 1,065 | 156 |  |
Net investment income | 448 | (183) |  |
Corporate and other expenses | (572) | (590) |  |
Income before income tax | 941 | (617) |  |
Attritional losses | (10,913) | (13,128) |  |
CAT losses | 0 | 0 |  |
Prior year adverse (favorable) loss development | (567) | (1) | $ (567) | $ (1)
Total net loss and LAE incurred | 10,346 | 13,127 |  |
Total allocated assets | $ 145,402 | $ 92,939 |  |

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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 49 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482785/280-10-55-49 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 280 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 18 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482810/280-10-50-18 + Details
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- Definition Costs incurred during the period, such as those relating to general administration and policy maintenance that do not vary with and are not primarily related to the acquisition or renewal of insurance contracts. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(7)(b)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 944 -SubTopic 720 -Section 25 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477550/944-720-25-2 + Details
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- Definition Amount, after effects of policies assumed or ceded, of expense related to the provision for policy benefits and costs incurred. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(5)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
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- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 55 -Paragraph 7 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480046/944-40-55-7 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480081/944-40-50-3 + Details
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