Future policy benefits (Premiums & interest) (Details) - Segment Life [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	$ 1,470	$ 1,140
Interest Accretion	86	71
Term Life Insurance
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	167	160
Interest Accretion	5	4
Whole Life Insurance
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	530	230
Interest Accretion	47	34
Accident and Health Insurance Product Line [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	753	733
Interest Accretion	31	31
Insurance, Other
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	20	17
Interest Accretion	$ 3	$ 2