XML 47 R35.htm IDEA: XBRL DOCUMENT v3.25.3
Investments - Schedule of Aging of Unrealized Losses (Details)
$ in Thousands
Sep. 30, 2025
USD ($)
security
Dec. 31, 2024
USD ($)
security
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 23 98
Fair value, less than 12 months $ 109,553 $ 486,314
Unrealized losses, less than 12 months $ (420) $ (7,848)
Number of securities,12 months or greater | security 414 474
Fair value, 12 months or greater $ 1,392,691 $ 1,578,701
Unrealized loss position, 12 months or greater $ (95,089) $ (150,774)
Number of securities, total | security 437 572
Fair Value $ 1,502,244 $ 2,065,015
Unrealized Losses $ (95,509) $ (158,622)
U.S. Treasury securities and obligations of U.S. government agencies    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 1 4
Fair value, less than 12 months $ 125 $ 8,002
Unrealized losses, less than 12 months   $ (98)
Number of securities,12 months or greater | security 7 9
Fair value, 12 months or greater $ 10,819 $ 11,510
Unrealized loss position, 12 months or greater $ (165) $ (391)
Number of securities, total | security 8 13
Fair Value $ 10,944 $ 19,512
Unrealized Losses $ (165) $ (489)
Municipal debt securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 1 25
Fair value, less than 12 months $ 893 $ 110,648
Unrealized losses, less than 12 months $ (3) $ (1,928)
Number of securities,12 months or greater | security 221 220
Fair value, 12 months or greater $ 478,460 $ 471,770
Unrealized loss position, 12 months or greater $ (30,961) $ (47,939)
Number of securities, total | security 222 245
Fair Value $ 479,353 $ 582,418
Unrealized Losses $ (30,964) $ (49,867)
Corporate debt securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 15 68
Fair value, less than 12 months $ 64,253 $ 366,113
Unrealized losses, less than 12 months $ (378) $ (5,822)
Number of securities,12 months or greater | security 170 226
Fair value, 12 months or greater $ 866,782 $ 1,053,862
Unrealized loss position, 12 months or greater $ (61,204) $ (100,319)
Number of securities, total | security 185 294
Fair Value $ 931,035 $ 1,419,975
Unrealized Losses $ (61,582) $ (106,141)
Asset-backed securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 3 0
Fair value, less than 12 months $ 13,133 $ 0
Unrealized losses, less than 12 months $ (37) $ 0
Number of securities,12 months or greater | security 16 19
Fair value, 12 months or greater $ 36,630 $ 41,559
Unrealized loss position, 12 months or greater $ (2,759) $ (2,125)
Number of securities, total | security 19 19
Fair Value $ 49,763 $ 41,559
Unrealized Losses $ (2,796) $ (2,125)
Short-term investments    
Debt Securities, Available-for-sale [Line Items]    
Number of securities, less than 12 months | security 3 1
Fair value, less than 12 months $ 31,149 $ 1,551
Unrealized losses, less than 12 months $ (2)  
Number of securities,12 months or greater | security 0 0
Fair value, 12 months or greater $ 0 $ 0
Unrealized loss position, 12 months or greater $ 0 $ 0
Number of securities, total | security 3 1
Fair Value $ 31,149 $ 1,551
Unrealized Losses $ (2)