Accounts Receivable - Components of Accounts Receivable (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Current:
Patient accounts receivable	$ 666.6	$ 563.0
Other accounts receivable	13.7	9.8
Accounts receivable, current	680.3	572.8
Noncurrent patient accounts receivable	83.5	123.8
Accounts receivable	$ 763.8	$ 696.6