Investments - Schedule of Investment Portfolio Operating and Balance Sheet Data (Details) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
Jun. 30, 2026 |
Dec. 31, 2025 |
Jun. 30, 2025 |
Dec. 31, 2024 |
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| Income Statement [Abstract] | ||||||||
| Expenses | $ (20,052) | $ (17,373) | $ (50,983) | $ (47,075) | ||||
| Income tax expense | 3,738 | (3,525) | (1,514) | (8,585) | ||||
| Net increase in net assets resulting from operations | 48,593 | 34,809 | 106,571 | 99,280 | ||||
| Balance Sheet Related Disclosures [Abstract] | ||||||||
| Stockholders’ equity | 1,530,292 | 1,371,087 | 1,530,292 | 1,371,087 | $ 1,479,902 | $ 1,418,357 | $ 1,319,892 | $ 1,231,208 |
| Clarion Safety Systems, LLC | ||||||||
| Income Statement [Abstract] | ||||||||
| Revenues | 9,737 | 8,499 | 28,541 | 23,777 | ||||
| Expenses | (7,763) | (6,841) | (22,637) | (20,330) | ||||
| Income before taxes | 1,974 | 1,658 | 5,904 | 3,447 | ||||
| Income tax expense | (532) | (454) | (1,598) | (945) | ||||
| Net increase in net assets resulting from operations | 1,442 | 1,204 | 4,306 | 2,502 | ||||
| Balance Sheet Related Disclosures [Abstract] | ||||||||
| Current assets | 17,058 | 17,058 | 16,070 | |||||
| Non-current assets | 82,006 | 82,006 | 82,914 | |||||
| Current liabilities | 2,727 | 2,727 | 4,963 | |||||
| Non-current liabilities | 25,034 | 25,034 | 23,524 | |||||
| Stockholders’ equity | $ 71,303 | $ 71,303 | $ 70,497 | |||||
| Ownership percentage | 94.00% | 94.00% | 95.00% | |||||
| Sill Holdings, LLC | ||||||||
| Income Statement [Abstract] | ||||||||
| Revenues | $ 12,485 | 8,031 | $ 34,276 | 29,876 | ||||
| Expenses | (10,807) | (7,922) | (31,339) | (25,571) | ||||
| Income before taxes | 1,678 | 109 | 2,937 | 4,305 | ||||
| Income tax expense | (277) | 375 | (540) | (327) | ||||
| Net increase in net assets resulting from operations | 1,401 | $ 484 | 2,397 | $ 3,978 | ||||
| Balance Sheet Related Disclosures [Abstract] | ||||||||
| Current assets | 16,539 | 16,539 | $ 13,812 | |||||
| Non-current assets | 108,906 | 108,906 | 109,240 | |||||
| Current liabilities | 5,880 | 5,880 | 6,946 | |||||
| Non-current liabilities | 18,654 | 18,654 | 18,186 | |||||
| Stockholders’ equity | $ 100,911 | $ 100,911 | $ 97,920 | |||||
| Ownership percentage | 94.00% | 94.00% | 93.00% | |||||
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- Definition Investment Owned Percentage No definition available.
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- Definition Amount of asset recognized for present right to economic benefit, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Total obligations incurred as part of normal operations that are expected to be paid during the following twelve months or within one business cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of obligation due after one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The portion of profit or loss for the period, net of income taxes, which is attributable to the parent. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of equity (deficit) attributable to parent. Excludes temporary equity and equity attributable to noncontrolling interest. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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