Unaudited Interim Consolidated Statements of Financial Position (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Fixed Maturities, Available-for-sale, allowance for credit losses	$ 1,650	$ 2,008
Fixed Maturities, Available-for-sale, amortized cost	29,821,440	27,538,066
Fixed maturities, trading, amortized cost	3,942,046	3,476,746
Equity securities, at cost	575,867	824,270
Commercial mortgage and other loans, allowance for credit losses	42,682	37,689
Other invested assets, at fair value	$ 96,618	$ 85,025
Common Stock, Par or Stated Value Per Share	$ 10	$ 10
Common Stock, Shares Authorized	1,000,000	1,000,000
Common Stock, Shares, Issued	250,000	250,000
Common Stock, Shares, Outstanding	250,000	250,000