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Investments - Summary of Amortized Cost and Estimated Fair Value of Available-for-Sale Investments, Excluding VIE Investments (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024 | Sep. 30, 2024
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Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | $ 61,582 | $ 119,024 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 | $ 0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 1,181 | 260 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 7,750 | 51,012 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 71 | 792 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 53,832 | 68,012 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 2,616 | 4,559 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 2,687 | 5,351 |
Debt Securities, Available-for-Sale | 426,926 |  |
Debt Securities, Available-for-sale, Amortized Cost | 428,432 | 289,712 |
Debt Securities, Available-for-Sale, Current | 426,926 | 284,621 |
Short-term Investments [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 0 | 0 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 10 | 13 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 0 | 0 |
Debt Securities, Available-for-Sale | 295,825 | 127,601 |
Debt Securities, Available-for-sale, Amortized Cost | 295,815 | 127,588 |
Fixed Income Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 61,582 | 119,024 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 1,171 | 247 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 7,750 | 51,012 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 71 | 792 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 53,832 | 68,012 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 2,616 | 4,559 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 2,687 | 5,351 |
Debt Securities, Available-for-Sale | 131,101 | 157,020 |
Debt Securities, Available-for-sale, Amortized Cost | 132,617 | 162,124 |
Fixed Income Securities [Member] | Municipal Bonds [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 6,509 | 12,624 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 100 | 7 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 318 | 6,042 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 15 | 112 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 6,191 | 6,582 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 264 | 458 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 279 | 570 |
Debt Securities, Available-for-Sale | 11,510 | 14,083 |
Debt Securities, Available-for-sale, Amortized Cost | 11,689 | 14,646 |
Fixed Income Securities [Member] | Corporate Debt Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 36,124 | 70,396 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 590 | 107 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 3,269 | 23,784 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 13 | 269 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 32,855 | 46,612 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 2,167 | 3,636 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 2,180 | 3,905 |
Debt Securities, Available-for-Sale | 70,690 | 89,192 |
Debt Securities, Available-for-sale, Amortized Cost | 72,280 | 92,990 |
Fixed Income Securities [Member] | US Government Debt Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 16,076 | 30,737 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 398 | 98 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 3,012 | 15,919 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 34 | 344 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 13,064 | 14,818 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 171 | 465 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 205 | 809 |
Debt Securities, Available-for-Sale | 39,171 | 40,995 |
Debt Securities, Available-for-sale, Amortized Cost | 38,978 | 41,706 |
Fixed Income Securities [Member] | Residential Mortgage-Backed Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 1,722 | 2,446 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 43 | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 2,446 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 29 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 1,722 | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 14 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 14 | 29 |
Debt Securities, Available-for-Sale | 3,294 | 2,446 |
Debt Securities, Available-for-sale, Amortized Cost | 3,265 | 2,475 |
Fixed Income Securities [Member] | Collateralized Debt Obligations [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 390 | 655 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 15 | 13 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 390 | 655 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 2 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 0 | 2 |
Debt Securities, Available-for-Sale | 2,319 | 3,142 |
Debt Securities, Available-for-sale, Amortized Cost | 2,304 | 3,131 |
Fixed Income Securities [Member] | Asset-backed Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 0 | 1,428 |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 24 | 14 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 0 | 1,428 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 0 | 2 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 0 | 2 |
Debt Securities, Available-for-Sale | 2,298 | 5,061 |
Debt Securities, Available-for-sale, Amortized Cost | 2,274 | 5,049 |
Fixed Income Securities [Member] | Commercial Mortgage Backed Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Unrealized Loss Position | 761 | 738 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months | 761 | 738 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | 9 | 34 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer | 0 | 0 |
Debt Securities, Available-for-sale, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 9 | 34 |
Debt Securities, Available-for-Sale | 1,819 |  |
Debt Securities, Available-for-sale, Amortized Cost | 1,827 |  |
Fixed Income Securities [Member] | Collateralized Mortgage Backed Securities [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Allowance for Credit Loss | 0 | 0 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax | 1 | 8 |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | 9 | 34 |
Debt Securities, Available-for-Sale | 1,819 | 2,101 |
Debt Securities, Available-for-sale, Amortized Cost | 1,827 | $ 2,127 |
Fixed Income Investments And Other Investments [Member] |  |  |
Debt Securities, Available-for-sale [Line Items] |  |  |
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax | $ 2,687 |  |

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