Insurance and Contractholder Liabilities - Future Policy Benefits - Interest Rates and Duration (Details)	Sep. 30, 2024	Sep. 30, 2023
Cigna Healthcare
Insurance and Contractholder Liabilities [Line Items]
Interest accretion rate	2.83%	2.85%
Current discount rate	4.50%	6.03%
Weighted average duration	9 years	7 years
Other Operations
Insurance and Contractholder Liabilities [Line Items]
Interest accretion rate	5.64%	5.64%
Current discount rate	4.81%	5.73%
Weighted average duration	11 years 3 months 18 days	10 years 10 months 24 days