v3.26.3
Fair Value Measurements (Tables)
 9 Months Ended
Sep. 30, 2026
Fair Value Disclosures [Abstract]  
Balances Of Assets Measured At Fair Value On A Recurring Basis
The following tables present the balances of assets measured at fair value on a recurring basis by level within the fair value hierarchy.

September 30, 2026
(dollars in thousands)Level 1Level 2Level 3Total
Assets:
Investments:
Fixed maturity securities, available-for-sale:
U.S. Treasury securities$— $5,792,654 $— $5,792,654 
U.S. government-sponsored enterprises— 1,582,349 — 1,582,349 
Obligations of states, municipalities, and political subdivisions— 3,375,628 — 3,375,628 
Foreign governments, agencies, and supranationals— 3,377,830 — 3,377,830 
Agency mortgage-backed securities— 2,949,749 — 2,949,749 
Non-agency mortgage-backed securities— 43,262 — 43,262 
Corporate and university bonds— 173,590 — 173,590 
Total fixed maturity securities, available-for-sale— 17,295,062 — 17,295,062 
Equity securities:
Insurance, banks, and other financial institutions4,937,280 — — 4,937,280 
Industrial, consumer, and all other8,173,403 — — 8,173,403 
Total equity securities13,110,683 — — 13,110,683 
Short-term investments, available-for-sale2,547,949 221,143 — 2,769,092 
Total investments$15,658,632 $17,516,205 $— $33,174,837 

December 31, 2025
(dollars in thousands)Level 1Level 2Level 3Total
Assets:
Investments:
Fixed maturity securities, available-for-sale:
U.S. Treasury securities$— $5,927,907 $— $5,927,907 
U.S. government-sponsored enterprises— 1,640,234 — 1,640,234 
Obligations of states, municipalities, and political subdivisions— 3,672,468 — 3,672,468 
Foreign governments, agencies, and supranationals— 3,374,915 — 3,374,915 
Agency mortgage-backed securities— 2,901,120 — 2,901,120 
Non-agency mortgage-backed securities— 65,758 — 65,758 
Corporate and university bonds— 215,584 — 215,584 
Total fixed maturity securities, available-for-sale— 17,797,986 — 17,797,986 
Equity securities:
Insurance, banks, and other financial institutions5,441,617 — — 5,441,617 
Industrial, consumer, and all other7,562,695 — — 7,562,695 
Total equity securities13,004,312 — — 13,004,312 
Short-term investments, available-for-sale1,843,163 190,499 — 2,033,662 
Total investments$14,847,475 $17,988,485 $— $32,835,960