Commitments and Contingencies - Litigation (Details) $ in Millions		9 Months Ended
	Oct. 19, 2015 hospital	Sep. 30, 2018 USD ($)
Amended complaint | SSH-Evansville
Commitments and Contingencies
Number of case managers identified as plaintiff | hospital	2
Professional liability claims
Commitments and Contingencies
Self insurance retention limit		$ 35.0
Professional liability claims | Minimum | Joint Venture Operations
Commitments and Contingencies
Self insurance retention limit		5.0
Professional liability claims | Maximum | Joint Venture Operations
Commitments and Contingencies
Self insurance retention limit		$ 20.0