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Fair Value of Financial Instruments - Assets and Liabilities Measured at Fair Value by Hierarchy Level (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | $ 139,121 | $ 203,693
Securitized residential mortgage loans held for investment at fair value | 717,227 | 0
Securitized nonrecourse debt | 703,526 | 0
Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 6,343,202 | 6,084,225
Derivative assets | 4,274 | 1,913
Mortgage servicing rights | 2,702 |
Securitized residential mortgage loans held for investment at fair value | 717,228 |
Total assets at fair value | 7,206,527 | 6,289,831
Derivative Liabilities | $ 1,289 | $ 1,509
Derivative Liability, Statement of Financial Position [Extensible Enumeration] | Other Liabilities | Other Liabilities
Securitized nonrecourse debt | $ 703,526 |
Total liabilities at fair value | 704,815 | $ 1,509
Level I | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 632,932 | 574,337
Derivative assets | 0 | 0
Mortgage servicing rights | 0 |
Securitized residential mortgage loans held for investment at fair value | 0 |
Total assets at fair value | 641,737 | 660,038
Derivative Liabilities | 0 | 0
Securitized nonrecourse debt | 0 |
Total liabilities at fair value | 0 | 0
Level II | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 5,697,816 | 5,500,192
Derivative assets | 4,274 | 1,912
Mortgage servicing rights | 0 |
Securitized residential mortgage loans held for investment at fair value | 717,228 |
Total assets at fair value | 6,549,634 | 5,620,096
Derivative Liabilities | 40 | 817
Securitized nonrecourse debt | 703,526 |
Total liabilities at fair value | 703,566 | 817
Level III | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 12,454 | 9,696
Derivative assets | 0 | 1
Mortgage servicing rights | 2,702 |
Securitized residential mortgage loans held for investment at fair value | 0 |
Total assets at fair value | 15,156 | 9,697
Derivative Liabilities | 1,249 | 692
Securitized nonrecourse debt | 0 |
Total liabilities at fair value | 1,249 | 692
Loaned securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 130,000 |
Loaned securities | Fair Value, Measurements, Recurring | U.S. government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities |  | 9,803
Loaned securities | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 130,256 | 117,992
Loaned securities | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 60 |
Loaned securities | Level I | Fair Value, Measurements, Recurring | U.S. government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities |  | 9,803
Loaned securities | Level I | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 0 | 0
Loaned securities | Level I | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 0 |
Loaned securities | Level II | Fair Value, Measurements, Recurring | U.S. government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities |  | 0
Loaned securities | Level II | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 130,256 | 117,992
Loaned securities | Level II | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 60 |
Loaned securities | Level III | Fair Value, Measurements, Recurring | U.S. government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities |  | 0
Loaned securities | Level III | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 0 | 0
Loaned securities | Level III | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 0 |
Fixed-maturities available for sale | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 5,074,920 | 5,188,228
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | U.S. government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 128,332 | 134,593
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 148,891 | 142,785
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 2,476,639 | 2,511,905
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | RMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 1,011,630 | 1,014,071
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 411,999 | 558,383
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | CLO |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 411,462 | 487,849
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 438,811 | 284,559
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | Foreign government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value |  | 5,087
Fixed-maturities available for sale | Fair Value, Measurements, Recurring | Mortgage insurance-linked notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 47,156 | 48,996
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 119,630 | 124,734
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | U.S. government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 119,630 | 124,734
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | RMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | CLO |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | Foreign government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value |  | 0
Fixed-maturities available for sale | Level I | Fair Value, Measurements, Recurring | Mortgage insurance-linked notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 4,955,290 | 5,063,494
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | U.S. government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 8,702 | 9,859
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 148,891 | 142,785
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 2,476,639 | 2,511,905
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | RMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 1,011,630 | 1,014,071
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 411,999 | 558,383
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | CLO |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 411,462 | 487,849
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 438,811 | 284,559
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | Foreign government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value |  | 5,087
Fixed-maturities available for sale | Level II | Fair Value, Measurements, Recurring | Mortgage insurance-linked notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 47,156 | 48,996
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | U.S. government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | RMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | CLO |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | Foreign government and agency securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value |  | 0
Fixed-maturities available for sale | Level III | Fair Value, Measurements, Recurring | Mortgage insurance-linked notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 82,652 | 106,423
Trading securities | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 50,845 | 70,844
Trading securities | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 23,940 | 24,913
Trading securities | Fair Value, Measurements, Recurring | RMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 3,029 | 5,930
Trading securities | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 4,838 | 4,736
Trading securities | Level I | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level I | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level I | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level I | Fair Value, Measurements, Recurring | RMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level I | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level II | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 82,652 | 106,423
Trading securities | Level II | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 50,845 | 70,844
Trading securities | Level II | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 23,940 | 24,913
Trading securities | Level II | Fair Value, Measurements, Recurring | RMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 3,029 | 5,930
Trading securities | Level II | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 4,838 | 4,736
Trading securities | Level III | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level III | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level III | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level III | Fair Value, Measurements, Recurring | RMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Trading securities | Level III | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Equity securities | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 138,189 | 89,057
Equity securities | Level I | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 128,368 | 81,170
Equity securities | Level II | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 3,275 | 5,387
Equity securities | Level III | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 6,546 | 2,500
Equity securities | Loaned securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 9,000 |
Equity securities | Loaned securities | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 8,805 | 75,898
Equity securities | Loaned securities | Level I | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 8,805 | 75,898
Equity securities | Loaned securities | Level II | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 0 | 0
Equity securities | Loaned securities | Level III | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 0 | 0
Residential mortgage loans held for sale | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 519,885 | 32,755
Residential mortgage loans held for sale | Level I | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Residential mortgage loans held for sale | Level II | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 519,885 | 32,755
Residential mortgage loans held for sale | Level III | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Other invested assets | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 5,908 | 7,196
Other invested assets | Level I | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Other invested assets | Level II | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Other invested assets | Level III | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 5,908 | 7,196
Short-term investments | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 521,648 | 660,566
Short-term investments | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 1,750 | 2,700
Short-term investments | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 49,905 | 150,930
Short-term investments | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value |  | 1,347
Short-term investments | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 16,054 | 1,158
Short-term investments | Fair Value, Measurements, Recurring | Other investments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 69,005 | 135,998
Short-term investments | Fair Value, Measurements, Recurring | Money market instruments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 384,934 | 368,433
Short-term investments | Level I | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 384,934 | 368,433
Short-term investments | Level I | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level I | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level I | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value |  | 0
Short-term investments | Level I | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level I | Fair Value, Measurements, Recurring | Other investments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level I | Fair Value, Measurements, Recurring | Money market instruments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 384,934 | 368,433
Short-term investments | Level II | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 136,714 | 292,133
Short-term investments | Level II | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 1,750 | 2,700
Short-term investments | Level II | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 49,905 | 150,930
Short-term investments | Level II | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value |  | 1,347
Short-term investments | Level II | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 16,054 | 1,158
Short-term investments | Level II | Fair Value, Measurements, Recurring | Other investments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 69,005 | 135,998
Short-term investments | Level II | Fair Value, Measurements, Recurring | Money market instruments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level III | Fair Value, Measurements, Recurring |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level III | Fair Value, Measurements, Recurring | State and municipal obligations |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level III | Fair Value, Measurements, Recurring | Corporate bonds and notes |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level III | Fair Value, Measurements, Recurring | CMBS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value |  | 0
Short-term investments | Level III | Fair Value, Measurements, Recurring | Other ABS |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level III | Fair Value, Measurements, Recurring | Other investments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Level III | Fair Value, Measurements, Recurring | Money market instruments |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Total investments at fair value | 0 | 0
Short-term investments | Loaned securities |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Loaned securities | 464 |
Partnership investments | Carrying Amount |  |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] |  |
Other invested assets | $ 2,000 | $ 1,000

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