Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Assets:
Fixed maturities, available for sale, amortized cost	$ 18,948,357	$ 18,835,809
Fixed maturities, available for sale, allowance for credit losses	10,415	10,395
Other long-term investments under fair value option	1,285,697	1,235,759
Liabilities:
Future policy benefits at original rates	17,933,726	17,552,564
Total long-term debt, fair value	$ 2,196,342	$ 2,122,772
Shareholders' equity:
Preferred stock, par value (in dollars per share)	$ 1	$ 1
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	320,000,000	320,000,000
Common stock, shares issued (in shares)	97,218,183	97,218,183
Common stock, shares outstanding (in shares)	97,218,183	97,218,183
Treasury stock, at cost (in shares)	16,908,676	13,240,616
Investment funds
Assets:
Other long-term investments under fair value option	$ 1,037,447	$ 986,766