Insurance Liabilities - Balances of changes in liability for future policy benefits (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Jan. 01, 2021
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	$ 14,574	$ 15,643
Effect of changes in discount rate assumptions (AOCI)	2,200	(856)
Beginning balance at original discount rate	16,774	14,787
Effect of changes in cash flow assumptions			$ 0	$ 0
Effect of actual variances from expected experience			6	31
Adjusted beginning of year balance	16,780	14,818
Issuances	364	379
Interest accrual	129	113
Net premium collected	(446)	(389)
Foreign exchange impact	88	(140)
Other	3	0
Ending balance at original discount rate	16,918	14,781
Effect of changes in discount rate assumptions (AOCI)	(2,049)	(284)
Balance, end of period	14,869	14,497
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Beginning balance	57,886	70,643
Effect of changes in discount rate assumptions (AOCI)	7,672	(9,401)
Beginning balance at original discount rate	65,558	61,242
Adjustments			0	0
Effect of actual variances from expected experience			15	22
Adjusted beginning of year balance	65,573	61,264
Issuances	1,879	655
Interest accrual	648	601
Benefit payments	(1,182)	(1,139)
Foreign exchange impact	392	(271)
Other	(2)	0
Ending balance at original discount rate	67,308	61,110
Effect of changes in discount rate assumptions (AOCI)	(6,470)	2,325
Ending balance	60,838	63,435
Net liability for future policy benefits, end of period	45,969	48,938
Liability for future policy benefits for certain participating contracts	1,340	1,386
Liability for universal life policies with secondary guarantees and similar features	3,512	4,223
Deferred profit liability	2,396	2,232
Other reconciling items	1,629	2,528
Future policy benefits for life and accident and health insurance contracts	54,846	59,307	51,914		$ 67,364
Less: Reinsurance recoverable:	(24,266)	(29,342)
Net liability for future policy benefits after reinsurance recoverable	30,580	29,965
Individual Retirement
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	0	0
Effect of changes in discount rate assumptions (AOCI)	0	0
Beginning balance at original discount rate	0	0
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected experience			1	0
Adjusted beginning of year balance	1	0
Issuances	6	4
Interest accrual	0	0
Net premium collected	(7)	(4)
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	0	0
Effect of changes in discount rate assumptions (AOCI)	0	0
Balance, end of period	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Beginning balance	1,223	1,373
Effect of changes in discount rate assumptions (AOCI)	167	(95)
Beginning balance at original discount rate	1,390	1,278
Adjustments			0	0
Effect of actual variances from expected experience			(3)	1
Adjusted beginning of year balance	1,387	1,279
Issuances	70	50
Interest accrual	12	10
Benefit payments	(32)	(28)
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	1,437	1,311
Effect of changes in discount rate assumptions (AOCI)	(141)	(24)
Ending balance	1,296	1,287
Net liability for future policy benefits, end of period	$ 1,296	$ 1,287
Weighted average liability duration of the liability for future policy benefits (in years)	7 years 8 months 12 days	8 years 1 month 6 days
Group Retirement
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	$ 0	$ 0
Effect of changes in discount rate assumptions (AOCI)	0	0
Beginning balance at original discount rate	0	0
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected experience			0	0
Adjusted beginning of year balance	0	0
Issuances	0	0
Interest accrual	0	0
Net premium collected	0	0
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	0	0
Effect of changes in discount rate assumptions (AOCI)	0	0
Balance, end of period	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Beginning balance	211	264
Effect of changes in discount rate assumptions (AOCI)	2	(46)
Beginning balance at original discount rate	213	218
Adjustments			0	0
Effect of actual variances from expected experience			(1)	(2)
Adjusted beginning of year balance	212	216
Issuances	2	5
Interest accrual	3	3
Benefit payments	(7)	(8)
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	210	216
Effect of changes in discount rate assumptions (AOCI)	3	25
Ending balance	213	241
Net liability for future policy benefits, end of period	$ 213	$ 241
Weighted average liability duration of the liability for future policy benefits (in years)	7 years 1 month 6 days	7 years 4 months 24 days
Life Insurance
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	$ 11,654	$ 14,369
Effect of changes in discount rate assumptions (AOCI)	1,872	(706)
Beginning balance at original discount rate	13,526	13,663
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected experience			12	29
Adjusted beginning of year balance	13,538	13,692
Issuances	322	375
Interest accrual	106	100
Net premium collected	(352)	(355)
Foreign exchange impact	96	(140)
Other	3	0
Ending balance at original discount rate	13,713	13,672
Effect of changes in discount rate assumptions (AOCI)	(1,648)	(339)
Balance, end of period	12,065	13,333
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Beginning balance	21,179	27,442
Effect of changes in discount rate assumptions (AOCI)	3,424	(2,717)
Beginning balance at original discount rate	24,603	24,725
Adjustments			0	0
Effect of actual variances from expected experience			26	38
Adjusted beginning of year balance	24,629	24,763
Issuances	318	374
Interest accrual	224	221
Benefit payments	(476)	(523)
Foreign exchange impact	277	(178)
Other	1	(1)
Ending balance at original discount rate	24,973	24,656
Effect of changes in discount rate assumptions (AOCI)	(3,081)	170
Ending balance	21,892	24,826
Net liability for future policy benefits, end of period	$ 9,827	$ 11,493
Weighted average liability duration of the liability for future policy benefits (in years)	12 years 4 months 24 days	13 years 7 months 6 days
Institutional Markets
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	$ 0	$ 0
Effect of changes in discount rate assumptions (AOCI)	0	0
Beginning balance at original discount rate	0	0
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected experience			0	0
Adjusted beginning of year balance	0	0
Issuances	0	0
Interest accrual	0	0
Net premium collected	0	0
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	0	0
Effect of changes in discount rate assumptions (AOCI)	0	0
Balance, end of period	0	0
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Beginning balance	12,464	13,890
Effect of changes in discount rate assumptions (AOCI)	2,634	(870)
Beginning balance at original discount rate	15,098	13,020
Adjustments			0	0
Effect of actual variances from expected experience			(5)	(5)
Adjusted beginning of year balance	15,093	13,015
Issuances	1,450	223
Interest accrual	139	105
Benefit payments	(228)	(198)
Foreign exchange impact	125	(93)
Other	0	1
Ending balance at original discount rate	16,579	13,053
Effect of changes in discount rate assumptions (AOCI)	(2,302)	(551)
Ending balance	14,277	12,502
Net liability for future policy benefits, end of period	$ 14,277	$ 12,502
Weighted average liability duration of the liability for future policy benefits (in years)	11 years 6 months	12 years 1 month 6 days
Other Operations before consolidation and eliminations
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	$ 991	$ 1,274
Effect of changes in discount rate assumptions (AOCI)	66	(150)
Beginning balance at original discount rate	1,057	1,124
Effect of changes in cash flow assumptions			0	0
Effect of actual variances from expected experience			3	2
Adjusted beginning of year balance	1,060	1,126
Issuances	0	0
Interest accrual	12	13
Net premium collected	(30)	(30)
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	1,042	1,109
Effect of changes in discount rate assumptions (AOCI)	(48)	55
Balance, end of period	994	1,164
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Beginning balance	20,429	27,674
Effect of changes in discount rate assumptions (AOCI)	1,083	(5,673)
Beginning balance at original discount rate	21,512	22,001
Adjustments			0	0
Effect of actual variances from expected experience			0	$ (10)
Adjusted beginning of year balance	21,512	21,991
Issuances	3	3
Interest accrual	257	262
Benefit payments	(379)	(382)
Foreign exchange impact	0	0
Other	(3)	0
Ending balance at original discount rate	21,390	21,874
Effect of changes in discount rate assumptions (AOCI)	(492)	2,705
Ending balance	20,898	24,579
Net liability for future policy benefits, end of period	$ 19,904	$ 23,415
Weighted average liability duration of the liability for future policy benefits (in years)	11 years 7 months 6 days	12 years 9 months 18 days
General Insurance
Liability for Future Policy Benefit, Expected Net Premium [Roll Forward]
Balance, beginning of year	$ 1,929
Effect of changes in discount rate assumptions (AOCI)	262
Beginning balance at original discount rate	2,191
Effect of changes in cash flow assumptions			0
Effect of actual variances from expected experience			(10)
Adjusted beginning of year balance	2,181
Issuances	36
Interest accrual	11
Net premium collected	(57)
Foreign exchange impact	(8)
Other	0
Ending balance at original discount rate	2,163
Effect of changes in discount rate assumptions (AOCI)	(353)
Balance, end of period	1,810
Liability for Future Policy Benefit, Expected Future Policy Benefit [Roll Forward]
Beginning balance	2,380
Effect of changes in discount rate assumptions (AOCI)	362
Beginning balance at original discount rate	2,742
Adjustments			0
Effect of actual variances from expected experience			$ (2)
Adjusted beginning of year balance	2,740
Issuances	36
Interest accrual	13
Benefit payments	(60)
Foreign exchange impact	(10)
Other	0
Ending balance at original discount rate	2,719
Effect of changes in discount rate assumptions (AOCI)	(457)
Ending balance	2,262
Net liability for future policy benefits, end of period	$ 452
Weighted average liability duration of the liability for future policy benefits (in years)	10 years