Reinsurance - Summary of the composition of pool of assets (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2023		Mar. 31, 2022	Dec. 31, 2022		Jan. 01, 2021
Effects of Reinsurance [Line Items]
Bonds available for sale	[1]	$ 229,397			$ 226,156
Fixed maturity securities - fair value option	[1]	4,762			4,485
Loans		51,616			50,321
Investment real estate		2,199			2,153
Short-term investments	[1]	13,253			12,376
Derivative assets net, carrying value		616			514
Derivative assets, net, fair value		4,791			6,049
Other assets		12,967	[1]		12,384	[1]	$ 13,520
Total assets		536,627			522,228		$ 598,841
Carrying Value
Effects of Reinsurance [Line Items]
Short-term investments		6,387			6,668
Other assets		30			33
Hedge Funds and Private Equity Funds
Effects of Reinsurance [Line Items]
Fair Value Using NAV Per Share (or its equivalent)		11,852			11,809
Commercial mortgage loans
Effects of Reinsurance [Line Items]
Loans		37,779			37,128
Policy loans
Effects of Reinsurance [Line Items]
Loans		1,747			1,758
Fortitude Holdings
Effects of Reinsurance [Line Items]
Change in net unrealized gains (losses), gross		704		$ (3,300)
Change in net unrealized gains (losses), net of tax		556		$ (2,600)
Derivative asset, Fair value of collateral		278			192
Derivative liability, Fair value of collateral		24			28
Fortitude Holdings | Carrying Value
Effects of Reinsurance [Line Items]
Bonds available for sale		18,640			18,821
Fixed maturity securities - fair value option		4,406			4,182
Investment real estate		130			133
Short-term investments		184			75
Funds withheld investment assets		29,758			29,566
Derivative assets net, carrying value		80			90
Other assets		570			782
Total assets		30,408			30,438
Fortitude Holdings | Estimated Fair Value
Effects of Reinsurance [Line Items]
Bonds available for sale		18,640			18,821
Fixed maturity securities - fair value option		4,406			4,182
Investment real estate		315			348
Short-term investments		184			75
Funds withheld investment assets		29,718			29,511
Derivative assets, net, fair value		80			90
Other assets		570			782
Total		30,368			30,383
Fortitude Holdings | Hedge Funds and Private Equity Funds | Carrying Value
Effects of Reinsurance [Line Items]
Fair Value Using NAV Per Share (or its equivalent)		1,901			1,893
Fortitude Holdings | Hedge Funds and Private Equity Funds | Estimated Fair Value
Effects of Reinsurance [Line Items]
Fair Value Using NAV Per Share (or its equivalent)		1,901			1,893
Fortitude Holdings | Commercial mortgage loans | Carrying Value
Effects of Reinsurance [Line Items]
Loans		4,152			4,107
Fortitude Holdings | Commercial mortgage loans | Estimated Fair Value
Effects of Reinsurance [Line Items]
Loans, fair value		3,927			3,837
Fortitude Holdings | Policy loans | Carrying Value
Effects of Reinsurance [Line Items]
Loans		345			355
Fortitude Holdings | Policy loans | Estimated Fair Value
Effects of Reinsurance [Line Items]
Loans, fair value		$ 345			$ 355

[1] See Note 9 for details of balances associated with variable interest entities.