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Fair Value Measurements - Schedule of Changes in Fair Value of Securities Using Level 3 Inputs (Details) - USD ($) $ in Thousands | 6 Months Ended
--- | ---
Jun. 30, 2024 | Jun. 30, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | $ 551,689 |
Fair value, ending balance | 571,389 |
Investments |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 551,689 | $ 349,255
Purchases | 40,266 | 98,299
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (12,067) | (8,709)
Transfers into Level 3 | 48,433 | 19,234
Transfers out of Level 3 | (58,958) | (3,579)
Fair value, ending balance | 571,389 | 455,170
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 478 | 95
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 1,705 | 735
Investments | Net realized and unrealized gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 470 | 95
Investments | Net investment income earned |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | (502) | (171)
Investments | Other Comprehensive Income (Loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in OCI | 2,058 | 746
Obligations of states and political subdivisions |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 7,834 | 6,661
Purchases | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (68) | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Fair value, ending balance | 7,654 | 6,716
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 0 | 62
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | (112) | (7)
Obligations of states and political subdivisions | Net realized and unrealized gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 0 | 62
Obligations of states and political subdivisions | Net investment income earned |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 0 | 0
Obligations of states and political subdivisions | Other Comprehensive Income (Loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in OCI | (112) | (7)
Corporate securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 297,332 | 187,980
Purchases | 5,261 | 58,586
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (7,269) | (5,535)
Transfers into Level 3 | 28,896 | 2,238
Transfers out of Level 3 | (31,434) | 0
Fair value, ending balance | 293,713 | 245,489
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 226 | 251
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 850 | 1,846
Corporate securities | Net realized and unrealized gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 218 | 251
Corporate securities | Net investment income earned |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | (494) | 112
Corporate securities | Other Comprehensive Income (Loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in OCI | 1,203 | 1,857
CLO and other ABS |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 245,313 | 153,342
Purchases | 30,119 | 39,713
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (4,726) | (3,153)
Transfers into Level 3 | 19,537 | 14,148
Transfers out of Level 3 | (27,524) | (953)
Fair value, ending balance | 263,720 | 201,926
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 39 | 17
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 969 | (1,168)
CLO and other ABS | Net realized and unrealized gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 39 | 17
CLO and other ABS | Net investment income earned |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | (7) | (20)
CLO and other ABS | Other Comprehensive Income (Loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in OCI | 969 | (1,168)
RMBS |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 0 |
Purchases | 4,886 |
Sales | 0 |
Issuances | 0 |
Settlements | 0 |
Transfers into Level 3 | 0 |
Transfers out of Level 3 | 0 |
Fair value, ending balance | 4,886 |
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 0 |
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 0 |
RMBS | Net realized and unrealized gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 0 |
RMBS | Net investment income earned |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 0 |
RMBS | Other Comprehensive Income (Loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in OCI | 0 |
CMBS |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 356 | 375
Purchases | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | (4) | (21)
Transfers into Level 3 | 0 | 2,848
Transfers out of Level 3 | 0 | (2,626)
Fair value, ending balance | 349 | 377
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 0 | 0
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | (2) | 64
CMBS | Net realized and unrealized gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 0 | 0
CMBS | Net investment income earned |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | (1) | (263)
CMBS | Other Comprehensive Income (Loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in OCI | (2) | 64
Common stock |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Fair value, beginning balance | 854 | 897
Purchases | 0 | 0
Sales | 0 | 0
Issuances | 0 | 0
Settlements | 0 | 0
Transfers into Level 3 | 0 | 0
Transfers out of Level 3 | 0 | 0
Fair value, ending balance | 1,067 | 662
Change in unrealized gains (losses) for the period included in earnings for assets held at period end | 213 | (235)
Change in unrealized gains (losses) for the period included in OCI for assets held at period end | 0 | 0
Common stock | Net realized and unrealized gains (losses) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 213 | (235)
Common stock | Net investment income earned |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in net income | 0 | 0
Common stock | Other Comprehensive Income (Loss) |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Total net gains (losses) for the period included in OCI | $ 0 | $ 0

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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482106/820-10-50-2 + Details
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