Future policy benefits (Premiums & interest) (Details) - Segment Life [Member] - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	$ 1,574	$ 1,470
Interest Accretion	99	86
Term Life Insurance
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	170	167
Interest Accretion	5	5
Whole Life Insurance
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	563	530
Interest Accretion	58	47
Accident and Health Insurance Product Line [Member]
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	752	753
Interest Accretion	32	31
Insurance, Other
Liability for Future Policy Benefit, Activity [Line Items]
Gross Premiums or Assessments	89	20
Interest Accretion	$ 4	$ 3