Medical Claims Payable - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2024
2025
Claims Development [Line Items]
Net incurred but not reported liabilities plus expected development on reported claims	$ 12,667
2024
Claims Development [Line Items]
Net incurred but not reported liabilities plus expected development on reported claims		$ 4,653
2023
Claims Development [Line Items]
Net incurred but not reported liabilities plus expected development on reported claims			$ 754