Significant Accounting Policies - Narrative (Details) people in Millions, patient in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2022 USD ($) people Segment store clinic state patient	Mar. 31, 2021 USD ($)
Significant Accounting Policies [Line Items]
Number of pharmacy plan members | people	110
Number of patients served per year | patient	1
Number of reportable segments | Segment	4
Expenses from transactions with related party	$ 15	$ 9
Other revenues from transactions with related party	21	18
Loss on assets held for sale	$ 41	$ 0
Heartland Healthcare Services
Significant Accounting Policies [Line Items]
Number of states in which entity operates | state	4
Retail/ LTC
Significant Accounting Policies [Line Items]
Number of retail locations (more than) | store	9,000
Number of walk in medical clinics | clinic	1,100
Health Care Benefits
Significant Accounting Policies [Line Items]
Number of people served | people	35
Number of states in which the Company has entered the individual public health insurance exchange | state	8
Loss on assets held for sale	$ 41