Employee Benefits - Schedule of funded status of the plans reconciled to the amount reported in the balance sheets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
U.S. Plans | Pension
Change in projected benefit obligation:
Benefit obligation, beginning of year	$ 4,795	$ 5,410
Service cost	5	5	$ 5
Interest cost	109	92	134
Actuarial gain (loss)	(1,082)	(384)
AIG assets	(19)	(18)
Plan assets	(174)	(174)
Plan amendment	0	0
Curtailments	0	0
Settlements	(157)	(135)
Foreign exchange effect	0	0
Other	(2)	(1)
Projected benefit obligation, end of year	3,475	4,795	5,410
Change in plan assets:
Fair value of plan assets, beginning of year	4,746	4,931
Actual return on plan assets, net of expenses	(1,070)	124
AIG contributions	19	18
Foreign exchange effect	0	0
Fair value of plan assets, end of year	3,345	4,746	4,931
Funded status, end of year	(130)	(49)
Amounts recognized in the balance sheet:
Assets	55	198
Liabilities	(185)	(247)
Total amounts recognized	(130)	(49)
Pre-tax amounts recognized in Accumulated other comprehensive income (loss):
Net gain (loss)	(1,279)	(1,162)
Prior service (cost) credit	0	0
Total amounts recognized	(1,279)	(1,162)
U.S. Plans | Pension | Defined Benefit Plan, Unfunded Plan
Change in projected benefit obligation:
Benefit obligation, beginning of year	247
Projected benefit obligation, end of year	186	247
U.S. Plans | Postretirement benefit plans
Change in projected benefit obligation:
Benefit obligation, beginning of year	174	191
Service cost	1	1	1
Interest cost	4	3	5
Actuarial gain (loss)	(36)	(10)
AIG assets	(12)	(11)
Plan assets	0	0
Plan amendment	0	0
Curtailments	0	0
Settlements	0	0
Foreign exchange effect	0	0
Other	0	0
Projected benefit obligation, end of year	131	174	191
Change in plan assets:
Fair value of plan assets, beginning of year	0	0
Actual return on plan assets, net of expenses	0	0
AIG contributions	12	11
Foreign exchange effect	0	0
Fair value of plan assets, end of year	0	0	0
Funded status, end of year	(131)	(174)
Amounts recognized in the balance sheet:
Assets	0	0
Liabilities	(131)	(174)
Total amounts recognized	(131)	(174)
Pre-tax amounts recognized in Accumulated other comprehensive income (loss):
Net gain (loss)	39	3
Prior service (cost) credit	0	0
Total amounts recognized	39	3
Non-US Plan | Pension
Change in projected benefit obligation:
Benefit obligation, beginning of year	1,157	1,231
Service cost	18	21	21
Interest cost	10	9	10
Actuarial gain (loss)	(183)	10
AIG assets	(8)	(9)
Plan assets	(26)	(30)
Plan amendment	1	0
Curtailments	0	0
Settlements	(3)	(9)
Foreign exchange effect	(139)	(66)
Other	(1)	0
Projected benefit obligation, end of year	826	1,157	1,231
Change in plan assets:
Fair value of plan assets, beginning of year	996	977
Actual return on plan assets, net of expenses	(133)	77
AIG contributions	42	48
Foreign exchange effect	(137)	(58)
Fair value of plan assets, end of year	731	996	977
Funded status, end of year	(95)	(161)
Amounts recognized in the balance sheet:
Assets	78	84
Liabilities	(173)	(245)
Total amounts recognized	(95)	(161)
Pre-tax amounts recognized in Accumulated other comprehensive income (loss):
Net gain (loss)	(70)	(119)
Prior service (cost) credit	(25)	(34)
Total amounts recognized	(95)	(153)
Non-US Plan | Pension | Defined Benefit Plan, Unfunded Plan
Change in projected benefit obligation:
Benefit obligation, beginning of year	204
Projected benefit obligation, end of year	143	204
Non-US Plan | Postretirement benefit plans
Change in projected benefit obligation:
Benefit obligation, beginning of year	47	71
Service cost	0	1	1
Interest cost	1	2	2
Actuarial gain (loss)	(14)	(17)
AIG assets	(1)	(1)
Plan assets	0	0
Plan amendment	0	(2)
Curtailments	0	(7)
Settlements	0	0
Foreign exchange effect	(1)	0
Other	0	0
Projected benefit obligation, end of year	32	47	71
Change in plan assets:
Fair value of plan assets, beginning of year	0	0
Actual return on plan assets, net of expenses	0	0
AIG contributions	1	1
Foreign exchange effect	0	0
Fair value of plan assets, end of year	0	0	$ 0
Funded status, end of year	(32)	(47)
Amounts recognized in the balance sheet:
Assets	0	0
Liabilities	(32)	(47)
Total amounts recognized	(32)	(47)
Pre-tax amounts recognized in Accumulated other comprehensive income (loss):
Net gain (loss)	24	11
Prior service (cost) credit	1	2
Total amounts recognized	$ 25	$ 13