Investments (Amortized Cost and Fair Value of Fixed Maturity Holdings by Industry Type) (Details) - USD ($) $ in Millions	Dec. 31, 2024		Dec. 31, 2023
Corporate Secturities by Investment Sector And Credit Rating [Line Items]
Available for Sale at Fair value - Amortized cost	$ 82,907		$ 64,977
Fixed maturity securities available-for-sale at fair value (amortized cost of $82,907 and $64,977; allowance for credit losses of $98 and $75)	77,617	[1]	60,467	[2]
Corporate Debt Securities [Member]
Corporate Secturities by Investment Sector And Credit Rating [Line Items]
Available for Sale at Fair value - Amortized cost	54,705		42,014
Fixed maturity securities available-for-sale at fair value (amortized cost of $82,907 and $64,977; allowance for credit losses of $98 and $75)	$ 50,991	[1]	$ 38,755	[2]
Percentage Of Total Available For Sales Securities	100.00%		100.00%
Financial Services Sector [Member] | Corporate Debt Securities [Member]
Corporate Secturities by Investment Sector And Credit Rating [Line Items]
Available for Sale at Fair value - Amortized cost	$ 17,905		$ 15,052
Fixed maturity securities available-for-sale at fair value (amortized cost of $82,907 and $64,977; allowance for credit losses of $98 and $75)	$ 16,673		$ 13,789
Percentage Of Total Available For Sales Securities	32.70%		35.60%
Commercial and Industrial Sector [Member] | Corporate Debt Securities [Member]
Corporate Secturities by Investment Sector And Credit Rating [Line Items]
Available for Sale at Fair value - Amortized cost	$ 28,267		$ 21,413
Fixed maturity securities available-for-sale at fair value (amortized cost of $82,907 and $64,977; allowance for credit losses of $98 and $75)	$ 26,476		$ 19,935
Percentage Of Total Available For Sales Securities	51.90%		51.40%
Utility Industry [Member] | Corporate Debt Securities [Member]
Corporate Secturities by Investment Sector And Credit Rating [Line Items]
Available for Sale at Fair value - Amortized cost	$ 8,533		$ 5,549
Fixed maturity securities available-for-sale at fair value (amortized cost of $82,907 and $64,977; allowance for credit losses of $98 and $75)	$ 7,842		$ 5,031
Percentage Of Total Available For Sales Securities	15.40%		13.00%

[1] Excludes limited partnerships that are measured at estimated fair value using the NAV per share (or its equivalent) as a practical expedient. As of December 31, 2024, the fair value of such investments was $966 million

[2] Excludes limited partnerships that are measured at estimated fair value using the NAV per share (or its equivalent) as a practical expedient. As of December 31, 2023, the fair value of such investments was $856 million.