| Segment Reporting [Text Block] |
Segment Reporting The Company operates as a single reportable segment, Insurance Operations, providing workers' compensation insurance through its wholly owned subsidiaries. The segment represents the Company's traditional business offered through its agents, including business originated from its strategic partnerships and alliances, and its direct-to-customer business. Revenues for the Insurance Operations segment are generated primarily from earned workers' compensation premiums, investment income, and realized and unrealized gains (losses) on investments. The Company does not have intra-entity sales or transfers. The Company considers an operating segment to be any component of its business whose operating results are regularly reviewed by the CODM (the Company's President and Chief Executive Officer) to make key decisions about resources to be allocated and to assess its performance. Performance is determined based on multiple measures, including net income, the Company’s combined ratio, and the Company’s adjusted stockholders' equity. Net income, which is reported on the Company's Consolidated Statements of Comprehensive Income (Loss), is a comprehensive measure used to determine the Company’s overall profitability. The combined ratio, which is a widely-used measure in the property and casualty insurance industry, is used to determine whether the Company is generating an underwriting profit or loss. Adjusted stockholders' equity, a non-GAAP measure of financial strength and overall performance, is used as a performance measure for PSUs and is defined as: Total stockholders' equity plus Deferred reinsurance gain - LPT Agreement less Accumulated other comprehensive income (loss), net of tax. The measurement of segment assets is reported on the Company's Consolidated Balance Sheet as Total assets. The accounting policies of the Insurance Operations segment are the same as those described in the Annual Report. Under ASU 2023-07, the Company is required to disclose segment reporting requirements even as a single reportable segment, which includes additional disclosures regarding profit and loss information, as well as a further breakdown of significant expenses. The following table summarizes the Company's written premiums and components of net income, and significant segment expenses. | | | | | | | | | | | | | | | | | Insurance Operations | | Total | | | (in millions) | | Three Months Ended June 30, 2026 | | | | | | Gross premiums written | | $ | 163.4 | | | $ | 163.4 | | | Net premiums written | | 162.0 | | | 162.0 | | | | | | | | Net premiums earned | | 174.1 | | | 174.1 | | | Net investment income | | 27.4 | | | 27.4 | | Net realized and unrealized losses on investments | | 18.7 | | | 18.7 | | | | | | | | | | | | | Total revenues | | 220.2 | | | 220.2 | | | | | | | | Losses and loss adjustment expenses | | 122.3 | | | 122.3 | | | Commission expense | | 22.2 | | | 22.2 | | Compensation-related expenses(1) | | 22.9 | | | 22.9 | | Information technology expenses(1) | | 2.9 | | | 2.9 | | Professional fees(1) | | 5.0 | | | 5.0 | | Depreciation and amortization expenses(1) | | 3.3 | | | 3.3 | | Other underwriting expenses(1)(2) | | 2.5 | | | 2.5 | | AO and other expense allocations(3) | | (8.5) | | | (8.5) | | Premium taxes and assessments | | 6.9 | | | 6.9 | | Policyholder dividends | | 0.8 | | | 0.8 | | CECL related to premiums receivable | | 3.9 | | | 3.9 | | Interest and financing expenses | | 1.3 | | | 1.3 | | | | | | | | Total expenses | | 185.5 | | | 185.5 | | | | | | | Net income before income taxes | | 34.7 | | | 34.7 | | Income tax | | 5.6 | | | 5.6 | | Net income (4) | | $ | 29.1 | | | $ | 29.1 | | | | | | | Combined ratio | | 105.8 | % | | 105.8 | % | | | | | | Adjusted stockholders' equity: | | | | | Stockholders’ equity | | $ | 858.8 | | | $ | 858.8 | | | Deferred reinsurance gain—LPT Agreement | | 85.3 | | | 85.3 | | | Accumulated other comprehensive loss, net of tax | | 12.2 | | | 12.2 | | | | | | | Adjusted stockholders' equity(5) | | $ | 956.3 | | | $ | 956.3 | | | | | | |
| | | | | | | | | | | | | | | | | Insurance Operations | | Total | | | (in millions) | | | | | | | Three Months Ended June 30, 2025 | | | | | | Gross premiums written | | $ | 203.3 | | | $ | 203.3 | | | Net premiums written | | 201.5 | | | 201.5 | | | | | | | | Net premiums earned | | 198.3 | | | 198.3 | | | Net investment income | | 27.1 | | | 27.1 | | | Net realized and unrealized gains on investments | | 20.9 | | | 20.9 | | | | | | | | | | | | | Total revenues | | 246.3 | | | 246.3 | | | | | | | | Losses and loss adjustment expenses | | 140.1 | | | 140.1 | | | Commission expense | | 26.1 | | | 26.1 | | Compensation-related expenses(1) | | 23.9 | | | 23.9 | | Information technology expenses(1) | | 2.8 | | | 2.8 | | Professional fees(1) | | 5.4 | | | 5.4 | | Depreciation and amortization expenses(1) | | 3.3 | | | 3.3 | | Other underwriting expenses(1)(2) | | 2.2 | | | 2.2 | | AO and other expense allocations(3) | | (9.3) | | | (9.3) | | Premium taxes and assessments | | 7.6 | | | 7.6 | | Policyholder dividends | | 2.2 | | | 2.2 | | | CECL related to premiums receivable | | 5.0 | | | 5.0 | | | | | | | | | | | | | Total expenses | | 209.3 | | | 209.3 | | | | | | | Net income before income taxes | | 37.0 | | | 37.0 | | Income tax expense | | 7.3 | | | 7.3 | | Net income(4) | | $ | 29.7 | | | $ | 29.7 | | | | | | | | Combined ratio | | 105.6 | % | | 105.6 | % | | | | | | Adjusted stockholders' equity: | | | | | Stockholders’ equity | | $ | 1,083.1 | | | $ | 1,083.1 | | | Deferred reinsurance gain—LPT Agreement | | 90.7 | | | 90.7 | | | Accumulated other comprehensive loss, net of tax | | 53.2 | | | 53.2 | | | | | | | Adjusted stockholders' equity(5) | | $ | 1,227.0 | | | $ | 1,227.0 | | | | | | |
| | | | | | | | | | | | | | | | | Insurance Operations | | Total | | | (in millions) | | Six Months Ended June 30, 2026 | | | | | | Gross premiums written | | $ | 344.2 | | | $ | 344.2 | | | Net premiums written | | 341.4 | | | 341.4 | | | | | | | | Net premiums earned | | 355.0 | | | 355.0 | | | Net investment income | | 55.7 | | | 55.7 | | Net realized and unrealized gains on investments | | 17.0 | | | 17.0 | | | | | | | Other income | | 0.1 | | | 0.1 | | | Total revenues | | 427.8 | | | 427.8 | | | | | | | | Losses and loss adjustment expenses | | 251.5 | | | 251.5 | | | Commission expense | | 45.9 | | | 45.9 | | Compensation-related expenses(1) | | 47.9 | | | 47.9 | | Information technology expenses(1) | | 5.6 | | | 5.6 | | Professional fees(1) | | 10.0 | | | 10.0 | | Depreciation and amortization expenses(1) | | 6.3 | | | 6.3 | | Other underwriting expenses(1)(2) | | 5.0 | | | 5.0 | | AO and other expense allocations(3) | | (17.0) | | | (17.0) | | Premium taxes and assessments | | 14.0 | | | 14.0 | | Policyholder dividends | | 1.9 | | | 1.9 | | | CECL related to premiums receivable | | 6.9 | | | 6.9 | | Interest and financing expenses | | 2.4 | | | 2.4 | | | | | | | | Total expenses | | 380.4 | | | 380.4 | | | | | | | Net income before income taxes | | 47.4 | | | 47.4 | | Income tax expense | | 8.2 | | | 8.2 | | Net income(4) | | $ | 39.2 | | | $ | 39.2 | | | | | | | | Combined ratio | | 106.4 | % | | 106.4 | % | | | | | | Adjusted stockholders' equity: | | | | | Stockholders’ equity | | $ | 858.8 | | | $ | 858.8 | | | Deferred reinsurance gain—LPT Agreement | | 85.3 | | | 85.3 | | | Accumulated other comprehensive loss, net of tax | | 12.2 | | | 12.2 | | Adjusted stockholders' equity(5) | | $ | 956.3 | | | $ | 956.3 | | | | | | |
| | | | | | | | | | | | | | | | | Insurance Operations | | Total | | | (in millions) | | Six Months Ended June 30, 2025 | | | | | | Gross premiums written | | $ | 415.4 | | | $ | 415.4 | | | Net premiums written | | 411.8 | | | 411.8 | | | | | | | | Net premiums earned | | 381.3 | | | 381.3 | | | Net investment income | | 59.2 | | | 59.2 | | Net realized and unrealized gains on investments | | 8.1 | | | 8.1 | | | | | | | Other income | | 0.3 | | | 0.3 | | | Total revenues | | 448.9 | | | 448.9 | | | | | | | | Losses and loss adjustment expenses | | 260.8 | | | 260.8 | | | Commission expense | | 49.1 | | | 49.1 | | Compensation-related expenses(1) | | 51.5 | | | 51.5 | | Information technology expenses(1) | | 5.8 | | | 5.8 | | Professional fees(1) | | 10.2 | | | 10.2 | | Depreciation and amortization expenses(1) | | 6.7 | | | 6.7 | | Other underwriting expenses(1)(2) | | 4.3 | | | 4.3 | | AO and other expense allocations(3) | | (19.9) | | | (19.9) | | Premium taxes and assessments | | 15.1 | | | 15.1 | | Policyholder dividends | | 5.0 | | | 5.0 | | | CECL related to premiums receivable | | 7.3 | | | 7.3 | | Interest and financing expenses | | 0.1 | | | 0.1 | | | | | | | | Total expenses | | 396.0 | | | 396.0 | | | | | | | Net income before income taxes | | 52.9 | | | 52.9 | | Income tax expense | | 10.4 | | | 10.4 | | Net income(4) | | $ | 42.5 | | | $ | 42.5 | | | | | | | | Combined ratio | | 103.9 | % | | 103.9 | % | | | | | | Adjusted stockholders' equity: | | | | | Stockholders’ equity | | $ | 1,083.1 | | | $ | 1,083.1 | | | Deferred reinsurance gain—LPT Agreement | | 90.7 | | | 90.7 | | | Accumulated other comprehensive loss, net of tax | | 53.2 | | | 53.2 | | Adjusted stockholders' equity(5) | | $ | 1,227.0 | | | $ | 1,227.0 | |
(1)Certain underwriting expenses are shown prior to adjusting and other (AO) and other expense allocations. (2)Other underwriting segment expenses include marketing and advertising, travel, corporate insurance, payment processing fees, and other miscellaneous expenses. (3)AO allocations consist of those underwriting expenses that relate to claims handling activities, which are allocated to loss adjustment expenses. Other allocations consist primarily of those underwriting expenses that relate to investing activities, which are allocated to net investment income, and nurse billing expenses that constitute defense and cost containment costs, which are allocated to loss adjustment expenses. (4)There are no reconciling adjustments to consolidated net income. (5)Adjusted stockholders' equity is a non-GAAP measure. Entity-Wide Disclosures The Company operates solely within the U.S. and does not have revenue from transactions with a single policyholder accounting for 10% or more of its revenues. Gross premiums written for the trailing twelve months (TTM) represent the past twelve consecutive months of the Company's new and renewal premiums including policy endorsements and final audit premiums. The Company's management focuses on TTM gross premiums written to evaluate financial performance and ensure a comprehensive assessment of growth and stability. Additionally, the Company focuses on policies in-force as they represent policies available for renewal in the future. The following table shows our gross premiums written for TTM, number of policies in-force for each of our largest states and all other states combined, plus or minus our additional premiums, which includes final audit premium accruals, non-compliant surcharges, and assigned risk premiums for the periods presented: | | | | | | | | | | | | | | | | | | | | | | | | | | | | | June 30, 2026 | | June 30, 2025 | | State | | Gross Premiums Written (TTM) | | Policies In-force | | Gross Premiums Written (TTM) | | Policies In-force | | | (dollars in millions) | | California | | $ | 309.7 | | | 43,641 | | | $ | 355.8 | | | 46,685 | | | Florida | | 53.7 | | | 10,912 | | | 66.0 | | | 11,278 | | | New York | | 36.2 | | | 7,793 | | | 37.6 | | | 7,878 | | Other (43 states and D.C.) | | 263.5 | | | 65,255 | | | 311.8 | | | 68,580 | | | Total excluding adjustments | | $ | 663.1 | | | 127,601 | | | $ | 771.2 | | | 134,421 | | Final audit premium accruals | | 7.2 | | | — | | | (13.0) | | | — | | | | | | | | | | | | | | | | | | | | Surcharges and assigned risk premiums | | 14.6 | | | — | | | 14.7 | | | — | | Total | | $ | 684.9 | | | 127,601 | | | $ | 772.9 | | | 134,421 | |
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