Insurance Liabilities - Balances of changes in liability for future policy benefits (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 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			(10)	(4)
Adjusted beginning of year balance	16,764	14,783
Issuances	733	728
Interest accrual	258	224
Net premium collected	(895)	(772)
Foreign exchange impact	118	(479)
Other	10	0
Ending balance at original discount rate	16,988	14,484
Effect of changes in discount rate assumptions (AOCI)	(2,295)	(1,190)
Balance, end of period	14,693	13,294
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			28	(37)
Adjusted beginning of year balance	65,586	61,205
Issuances	4,156	1,548
Interest accrual	1,320	1,293
Benefit payments	(2,403)	(2,110)
Foreign exchange impact	423	(928)
Other	(1)	(99)
Ending balance at original discount rate	69,081	60,909
Effect of changes in discount rate assumptions (AOCI)	(7,542)	(3,228)
Ending balance	61,539	57,681
Net liability for future policy benefits, end of period	46,846	44,387
Liability for future policy benefits for certain participating contracts	1,329	1,373
Liability for universal life policies with secondary guarantees and similar features	3,458	3,663
Deferred profit liability	2,451	2,199
Other reconciling items	1,606	2,222
Future policy benefits for life and accident and health insurance contracts	55,690	53,844	51,914		$ 67,364
Less: Reinsurance recoverable:	(23,765)	(26,677)
Net liability for future policy benefits after reinsurance recoverable	31,925	27,167
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			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	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			(1)	(7)
Adjusted beginning of year balance	1,389	1,271
Issuances	120	102
Interest accrual	25	20
Benefit payments	(65)	(56)
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	1,469	1,337
Effect of changes in discount rate assumptions (AOCI)	(158)	(109)
Ending balance	1,311	1,228
Net liability for future policy benefits, end of period	$ 1,311	$ 1,228
Weighted average liability duration of the liability for future policy benefits (in years)	7 years 9 months 18 days	7 years 8 months 12 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			0	(1)
Adjusted beginning of year balance	213	217
Issuances	6	7
Interest accrual	5	4
Benefit payments	(13)	(13)
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	211	215
Effect of changes in discount rate assumptions (AOCI)	(1)	10
Ending balance	210	225
Net liability for future policy benefits, end of period	$ 210	$ 225
Weighted average liability duration of the liability for future policy benefits (in years)	6 years 10 months 24 days	7 years 2 months 12 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			10	(8)
Adjusted beginning of year balance	13,536	13,655
Issuances	666	728
Interest accrual	214	199
Net premium collected	(719)	(710)
Foreign exchange impact	206	(479)
Other	10	0
Ending balance at original discount rate	13,913	13,393
Effect of changes in discount rate assumptions (AOCI)	(1,904)	(1,174)
Balance, end of period	12,009	12,219
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			36	(6)
Adjusted beginning of year balance	24,639	24,719
Issuances	656	726
Interest accrual	450	439
Benefit payments	(943)	(905)
Foreign exchange impact	236	(610)
Other	5	(1)
Ending balance at original discount rate	25,043	24,368
Effect of changes in discount rate assumptions (AOCI)	(3,386)	(1,868)
Ending balance	21,657	22,500
Net liability for future policy benefits, end of period	$ 9,648	$ 10,281
Weighted average liability duration of the liability for future policy benefits (in years)	12 years 6 months	12 years 8 months 12 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			17	(5)
Adjusted beginning of year balance	15,115	13,015
Issuances	3,301	708
Interest accrual	301	215
Benefit payments	(521)	(390)
Foreign exchange impact	308	(318)
Other	0	0
Ending balance at original discount rate	18,504	13,230
Effect of changes in discount rate assumptions (AOCI)	(2,752)	(1,712)
Ending balance	15,752	11,518
Net liability for future policy benefits, end of period	$ 15,752	$ 11,518
Weighted average liability duration of the liability for future policy benefits (in years)	11 years 7 months 6 days	11 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			6	4
Adjusted beginning of year balance	1,063	1,128
Issuances	0	0
Interest accrual	23	25
Net premium collected	(59)	(62)
Foreign exchange impact	0	0
Other	0	0
Ending balance at original discount rate	1,027	1,091
Effect of changes in discount rate assumptions (AOCI)	(61)	(16)
Balance, end of period	966	1,075
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			(8)	$ (18)
Adjusted beginning of year balance	21,504	21,983
Issuances	3	5
Interest accrual	513	615
Benefit payments	(739)	(746)
Foreign exchange impact	0	0
Other	(6)	(98)
Ending balance at original discount rate	21,275	21,759
Effect of changes in discount rate assumptions (AOCI)	(822)	451
Ending balance	20,453	22,210
Net liability for future policy benefits, end of period	$ 19,487	$ 21,135
Weighted average liability duration of the liability for future policy benefits (in years)	11 years 6 months	12 years
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			(26)
Adjusted beginning of year balance	2,165
Issuances	67
Interest accrual	21
Net premium collected	(117)
Foreign exchange impact	(88)
Other	0
Ending balance at original discount rate	2,048
Effect of changes in discount rate assumptions (AOCI)	(330)
Balance, end of period	1,718
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			$ (16)
Adjusted beginning of year balance	2,726
Issuances	70
Interest accrual	26
Benefit payments	(122)
Foreign exchange impact	(121)
Other	0
Ending balance at original discount rate	2,579
Effect of changes in discount rate assumptions (AOCI)	(423)
Ending balance	2,156
Net liability for future policy benefits, end of period	$ 438
Weighted average liability duration of the liability for future policy benefits (in years)	9 years 10 months 24 days