Future policy benefits (Premiums & interest) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	$ 1,510	$ 860
Interest Accretion	72	43
Term Life Insurance | Segment Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	170	49
Interest Accretion	3	2
Whole Life Insurance | Segment Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	162	74
Interest Accretion	33	26
Accident and Health Insurance Product Line [Member] | Segment Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	795	290
Interest Accretion	34	14
Accident and Health Insurance Product Line [Member] | Overseas General Insurance [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	364	365
Interest Accretion	0	0
Insurance, Other | Segment Life [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	19	82
Interest Accretion	$ 2	$ 1