Investments (Fixed Maturity Securities by Sector) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	$ 86,129	$ 83,395
Fixed maturity securities, allowance for credit losses	21	6	$ 11
Fixed maturity securities, gross unrealized gains	1,024	742
Fixed maturity securities, gross unrealized losses	7,047	9,374
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	80,085	74,757
U.S. corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	38,303	36,399
Fixed maturity securities, allowance for credit losses	15	1	2
Fixed maturity securities, gross unrealized gains	383	200
Fixed maturity securities, gross unrealized losses	3,332	4,436
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	35,339	32,162
Foreign corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	12,769	12,368
Fixed maturity securities, allowance for credit losses	0	1	7
Fixed maturity securities, gross unrealized gains	89	37
Fixed maturity securities, gross unrealized losses	1,276	1,912
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	11,582	10,492
U.S. government and agency
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	8,446	8,195
Fixed maturity securities, allowance for credit losses	0	0
Fixed maturity securities, gross unrealized gains	285	299
Fixed maturity securities, gross unrealized losses	517	596
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	8,214	7,898
RMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	8,127	8,384
Fixed maturity securities, allowance for credit losses	4	1	0
Fixed maturity securities, gross unrealized gains	48	44
Fixed maturity securities, gross unrealized losses	805	936
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	7,366	7,491
ABS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	6,509	5,647
Fixed maturity securities, allowance for credit losses	0	0
Fixed maturity securities, gross unrealized gains	23	3
Fixed maturity securities, gross unrealized losses	131	295
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	6,401	5,355
CMBS
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	6,940	7,239
Fixed maturity securities, allowance for credit losses	2	3	$ 2
Fixed maturity securities, gross unrealized gains	2	0
Fixed maturity securities, gross unrealized losses	601	699
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	6,339	6,537
State and political subdivision
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	3,958	4,015
Fixed maturity securities, allowance for credit losses	0	0
Fixed maturity securities, gross unrealized gains	153	120
Fixed maturity securities, gross unrealized losses	298	394
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	3,813	3,741
Foreign government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, amortized cost	1,077	1,148
Fixed maturity securities, allowance for credit losses	0	0
Fixed maturity securities, gross unrealized gains	41	39
Fixed maturity securities, gross unrealized losses	87	106
Fixed maturity securities available-for-sale, at estimated fair value (amortized cost: $73,144 and $71,285, respectively; allowance for credit losses of $20 and $4, respectively)	$ 1,031	$ 1,081