Revenue - Schedule of Revenue by Payor Type (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Disaggregation of Revenue [Line Items]
Revenue	$ 3,873,140	$ 3,147,698	$ 7,486,861	$ 6,025,827
Commercial Insurance
Disaggregation of Revenue [Line Items]
Revenue	1,112,500	786,100	2,126,800	1,502,000
Medicaid
Disaggregation of Revenue [Line Items]
Revenue	436,600	354,700	842,300	678,000
Medicare Part A
Disaggregation of Revenue [Line Items]
Revenue	309,800	264,700	618,700	527,500
Medicare Part B
Disaggregation of Revenue [Line Items]
Revenue	30,600	20,100	52,400	41,100
Medicare Part C
Disaggregation of Revenue [Line Items]
Revenue	720,500	590,200	1,387,500	1,110,500
Medicare Part D
Disaggregation of Revenue [Line Items]
Revenue	1,149,900	1,008,400	2,224,000	1,919,300
Private and Other
Disaggregation of Revenue [Line Items]
Revenue	113,200	123,500	235,200	247,400
Pharmacy Solutions
Disaggregation of Revenue [Line Items]
Revenue	3,407,100	2,790,100	6,578,500	5,322,300
Pharmacy Solutions \| Commercial Insurance
Disaggregation of Revenue [Line Items]
Revenue	1,053,500	742,000	2,012,900	1,416,500
Pharmacy Solutions \| Medicaid
Disaggregation of Revenue [Line Items]
Revenue	339,300	266,200	647,900	504,400
Pharmacy Solutions \| Medicare Part A
Disaggregation of Revenue [Line Items]
Revenue	136,300	138,900	274,000	279,300
Pharmacy Solutions \| Medicare Part B
Disaggregation of Revenue [Line Items]
Revenue	18,300	18,700	38,600	38,200
Pharmacy Solutions \| Medicare Part C
Disaggregation of Revenue [Line Items]
Revenue	653,700	555,600	1,256,100	1,043,300
Pharmacy Solutions \| Medicare Part D
Disaggregation of Revenue [Line Items]
Revenue	1,149,900	1,008,400	2,224,000	1,919,300
Pharmacy Solutions \| Private and Other
Disaggregation of Revenue [Line Items]
Revenue	56,100	60,300	125,000	121,300
Provider Services
Disaggregation of Revenue [Line Items]
Revenue	466,000	357,600	908,400	703,500
Provider Services \| Commercial Insurance
Disaggregation of Revenue [Line Items]
Revenue	59,000	44,100	113,900	85,500
Provider Services \| Medicaid
Disaggregation of Revenue [Line Items]
Revenue	97,300	88,500	194,400	173,600
Provider Services \| Medicare Part A
Disaggregation of Revenue [Line Items]
Revenue	173,500	125,800	344,700	248,200
Provider Services \| Medicare Part B
Disaggregation of Revenue [Line Items]
Revenue	12,300	1,400	13,800	2,900
Provider Services \| Medicare Part C
Disaggregation of Revenue [Line Items]
Revenue	66,800	34,600	131,400	67,200
Provider Services \| Private and Other
Disaggregation of Revenue [Line Items]
Revenue	$ 57,100	$ 63,200	$ 110,200	$ 126,100
Product Concentration Risk \| Revenue
Disaggregation of Revenue [Line Items]
% of Revenue	100.00%	100.00%	100.00%	100.00%
Product Concentration Risk \| Revenue \| Commercial Insurance
Disaggregation of Revenue [Line Items]
% of Revenue	28.70%	25.00%	28.40%	24.90%
Product Concentration Risk \| Revenue \| Medicaid
Disaggregation of Revenue [Line Items]
% of Revenue	11.30%	11.30%	11.30%	11.30%
Product Concentration Risk \| Revenue \| Medicare Part A
Disaggregation of Revenue [Line Items]
% of Revenue	8.00%	8.40%	8.30%	8.70%
Product Concentration Risk \| Revenue \| Medicare Part B
Disaggregation of Revenue [Line Items]
% of Revenue	0.80%	0.60%	0.70%	0.60%
Product Concentration Risk \| Revenue \| Medicare Part C
Disaggregation of Revenue [Line Items]
% of Revenue	18.60%	18.80%	18.60%	18.40%
Product Concentration Risk \| Revenue \| Medicare Part D
Disaggregation of Revenue [Line Items]
% of Revenue	29.70%	32.00%	29.70%	31.90%
Product Concentration Risk \| Revenue \| Private and Other
Disaggregation of Revenue [Line Items]
% of Revenue	2.90%	3.90%	3.00%	4.20%
Product Concentration Risk \| Revenue \| Pharmacy Solutions
Disaggregation of Revenue [Line Items]
% of Revenue	88.00%	88.60%	87.90%	88.30%
Product Concentration Risk \| Revenue \| Pharmacy Solutions \| Commercial Insurance
Disaggregation of Revenue [Line Items]
% of Revenue	27.20%	23.60%	26.90%	23.50%
Product Concentration Risk \| Revenue \| Pharmacy Solutions \| Medicaid
Disaggregation of Revenue [Line Items]
% of Revenue	8.80%	8.50%	8.70%	8.40%
Product Concentration Risk \| Revenue \| Pharmacy Solutions \| Medicare Part A
Disaggregation of Revenue [Line Items]
% of Revenue	3.50%	4.40%	3.70%	4.60%
Product Concentration Risk \| Revenue \| Pharmacy Solutions \| Medicare Part B
Disaggregation of Revenue [Line Items]
% of Revenue	0.50%	0.60%	0.50%	0.60%
Product Concentration Risk \| Revenue \| Pharmacy Solutions \| Medicare Part C
Disaggregation of Revenue [Line Items]
% of Revenue	16.90%	17.70%	16.80%	17.30%
Product Concentration Risk \| Revenue \| Pharmacy Solutions \| Medicare Part D
Disaggregation of Revenue [Line Items]
% of Revenue	29.70%	32.00%	29.70%	31.90%
Product Concentration Risk \| Revenue \| Pharmacy Solutions \| Private and Other
Disaggregation of Revenue [Line Items]
% of Revenue	1.40%	1.80%	1.60%	2.00%
Product Concentration Risk \| Revenue \| Provider Services
Disaggregation of Revenue [Line Items]
% of Revenue	12.00%	11.40%	12.10%	11.70%
Product Concentration Risk \| Revenue \| Provider Services \| Commercial Insurance
Disaggregation of Revenue [Line Items]
% of Revenue	1.50%	1.40%	1.50%	1.40%
Product Concentration Risk \| Revenue \| Provider Services \| Medicaid
Disaggregation of Revenue [Line Items]
% of Revenue	2.50%	2.80%	2.60%	2.90%
Product Concentration Risk \| Revenue \| Provider Services \| Medicare Part A
Disaggregation of Revenue [Line Items]
% of Revenue	4.50%	4.00%	4.60%	4.10%
Product Concentration Risk \| Revenue \| Provider Services \| Medicare Part B
Disaggregation of Revenue [Line Items]
% of Revenue	0.30%	0.00%	0.20%	0.00%
Product Concentration Risk \| Revenue \| Provider Services \| Medicare Part C
Disaggregation of Revenue [Line Items]
% of Revenue	1.70%	1.10%	1.80%	1.10%
Product Concentration Risk \| Revenue \| Provider Services \| Private and Other
Disaggregation of Revenue [Line Items]
% of Revenue	1.50%	2.10%	1.40%	2.20%