Future policy benefits (Premiums & interest) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	$ 3,035	$ 1,717
Interest Accretion	141	85
Term Life Insurance | Segment Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	339	172
Interest Accretion	6	4
Whole Life Insurance | Segment Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	487	173
Interest Accretion	70	53
Accident and Health Insurance Product Line [Member] | Segment Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	1,409	533
Interest Accretion	63	28
Accident and Health Insurance Product Line [Member] | Overseas General Insurance [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	768	705
Interest Accretion	0	0
Insurance, Other | Segment Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	32	134
Interest Accretion	$ 2	$ 0