Significant Accounting Policies - Narrative (Details) people in Millions, patient in Millions, $ in Millions	1 Months Ended	3 Months Ended
	Jan. 31, 2023 state	Mar. 31, 2023 USD ($) people clinic patient state store Segment	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Significant Accounting Policies [Line Items]
Number of pharmacy plan members | people		110
Number of patients served per year (more than) | patient		1
Number of reportable segments | Segment		4
Trade receivables		$ 9,229		$ 8,983
Contract liabilities (included in accrued expenses)		136	$ 80	71	$ 87
Expenses from transactions with related party		17	15
Other revenues from transactions with related party		19	$ 21
Other Insurance Liabilities
Significant Accounting Policies [Line Items]
Liability for future policy benefits		529		334
Other Long-Term Insurance Liabilities
Significant Accounting Policies [Line Items]
Liability for future policy benefits		$ 4,600		$ 4,700
Heartland Healthcare Services
Significant Accounting Policies [Line Items]
Number of states in which entity operates | state		4
Pharmacy & Consumer Wellness
Significant Accounting Policies [Line Items]
Number of retail locations (more than) | store		9,000
Health Services
Significant Accounting Policies [Line Items]
Number of walk in medical clinics (more than) | clinic		1,100
Health Care Benefits
Significant Accounting Policies [Line Items]
Number of people served | people		37
Number of states in which the Company has entered the individual public health insurance exchange | state		8
Additional number of states in which the Company entered the individual public health insurance exchange | state	4