Organization and Summary of Accounting Policies - Revenues by Sources (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total revenues	$ 3,114.3	$ 2,743.3	$ 2,539.3
Patient service revenues
Disaggregation of Revenue [Line Items]
Total revenues	$ 3,054.4	$ 2,700.4	$ 2,502.1
Patient service revenues \| Customer \| Revenue
Disaggregation of Revenue [Line Items]
Revenue by service type as a proportion of total revenues (percent)	100.00%	100.00%	100.00%
Private insurance
Disaggregation of Revenue [Line Items]
Total revenues	$ 1,634.2	$ 1,418.6	$ 1,288.0
Private insurance \| Customer \| Revenue
Disaggregation of Revenue [Line Items]
Revenue by service type as a proportion of total revenues (percent)	53.50%	52.50%	51.50%
Government
Disaggregation of Revenue [Line Items]
Total revenues	$ 1,256.8	$ 1,128.1	$ 1,059.2
Government \| Customer \| Revenue
Disaggregation of Revenue [Line Items]
Revenue by service type as a proportion of total revenues (percent)	41.10%	41.80%	42.30%
Self-pay
Disaggregation of Revenue [Line Items]
Total revenues	$ 82.3	$ 68.1	$ 65.9
Self-pay \| Customer \| Revenue
Disaggregation of Revenue [Line Items]
Revenue by service type as a proportion of total revenues (percent)	2.70%	2.50%	2.60%
Other
Disaggregation of Revenue [Line Items]
Total revenues	$ 81.1	$ 85.6	$ 89.0
Other \| Customer \| Revenue
Disaggregation of Revenue [Line Items]
Revenue by service type as a proportion of total revenues (percent)	2.70%	3.20%	3.60%
Other service revenues
Disaggregation of Revenue [Line Items]
Total revenues	$ 59.9	$ 42.9	$ 37.2
Other service revenues \| Related Party
Disaggregation of Revenue [Line Items]
Total revenues	$ 17.4	$ 18.4	$ 15.7