Related-Party Transactions - Additional Information (Details) - USD ($)
$ in Thousands
3 Months Ended 12 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Dec. 31, 2020
Dec. 31, 2019
Net medical claims incurred $ 214,432 $ 146,328 $ 590,468 $ 450,645
CarePoint Health Contract [Member]        
Net medical claims incurred $ 3,200 $ 2,700 $ 11,100 $ 9,700