Schedule II - Condensed Financial Information of Parent - Balance Sheets (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Investments:
Short-term investments under securities loan agreements, including collateral delivered	$ 1,042	$ 1,015
Deferred income taxes	2,134	2,160
Total assets	163,889	157,085
Liabilities:
Payables under securities loan and repurchase agreements, including collateral held	1,309	1,121
Short-term debt	399	1
Long-term debt	2,502	2,098
Derivatives	332	371
Shareholders' equity:
Preferred stock ($0.01 par value per share; $625 aggregate liquidation preference as of 2024 and 2023)	0	0
Common stock ($0.01 par value per share; 900,000,000 shares authorized; 105,592,281 and 103,584,699 shares issued as of 2024 and 2023, respectively; 95,497,265 and 102,854,569 shares outstanding as of 2024 and 2023, respectively)	1	1
Treasury stock (at cost; 10,095,016 and 730,130 shares as of 2024 and 2023, respectively)	(754)	(56)
Additional paid-in capital	6,266	6,143
Accumulated other comprehensive income (loss)	(2,462)	(2,400)	$ (3,055)
Retained earnings:
Unappropriated	954	505
Total shareholders' equity	5,788	5,878	$ 4,831	$ 9,668
Fixed maturities, amortized cost	$ 26,536	$ 27,690
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, aggregate liquidation preference	$ 625	$ 625
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	900,000,000	900,000,000
Common stock, shares issued	105,592,281	103,584,699
Common stock, shares outstanding	95,497,265	102,854,569	97,200,000	107,800,000
Treasury Stock, shares	10,095,016	730,130
Parent
Investments:
Fixed maturities, available-for-sale	$ 0	$ 6
Equity securities, at fair value	3	3
Short-term investments	20	13
Investment in subsidiaries	6	0
Derivatives	14	10
Investments In Subsidiaries	5,116	5,250
Total investments	5,159	5,282
Cash and cash equivalents	217	206
Short-term investments under securities loan agreements, including collateral delivered	1	1
Loans and Leases Receivable, Loans in Process	392	293
DueFromAffiliates	0	8
Deferred income taxes	819	856
Other assets	6	7
Total assets	6,594	6,653
Liabilities:
Payables under securities loan and repurchase agreements, including collateral held	0	10
Short-term debt	575	445
Long-term debt	1,871	1,865
Derivatives	22	9
Due to subsidiaries and affiliates	2	0
Other liabilities	119	131
Total liabilities	2,589	2,460
Retained earnings:
Unappropriated		505
Total shareholders' equity	4,005	4,193
Total liabilities and shareholders' equity	6,594	6,653
Fixed maturities, amortized cost	$ 0
Fixed maturities, including securities pledged, Amortized Cost Basis		$ 6