Subsequent Events (Narrative) (Details) $ in Millions					12 Months Ended
	Feb. 15, 2019 USD ($)	Jan. 31, 2019 USD ($) item	Jan. 08, 2019 USD ($)	Jan. 01, 2019 USD ($) item	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Subsequent Event [Line Items]
Proceeds from disposition of hospitals and other ancillary operations					$ 405	$ 1,692	$ 143
Subsequent Event [Member] | Mary Black Health System - Spartanburg and Gaffney [Member]
Subsequent Event [Line Items]
Definitive agreement date				Oct. 11, 2018
Proceeds from disposition of hospitals and other ancillary operations				$ 76
Subsequent Event [Member] | Mary Black Health System - Spartanburg [Member]
Subsequent Event [Line Items]
Number of licensed beds | item				207
Subsequent Event [Member] | Mary Black Health System - Gaffney [Member]
Subsequent Event [Line Items]
Number of licensed beds | item				125
Subsequent Event [Member] | Memorial Hospital of Salem County [Member]
Subsequent Event [Line Items]
Definitive agreement date		Mar. 15, 2018
Number of licensed beds | item		126
Proceeds from disposition of hospitals and other ancillary operations		$ 2
Credit Facility Type Of Debt Amendment No.1 [Member] | Revolving Credit Facility [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Line of credit facility, maximum borrowing capacity	$ 385
First lien net debt to EBITDA	5.00
First lien net debt to current earnings in period one	5.25
First lien net debt to current earnings in period two	5.00
First lien net debt to current earnings in period three	4.50
First Lien net Debt to Current Earnings in Period Four	4.25
Aggregate principal amount for springing maturity	$ 250
Credit Facility, Term Loan H [Member] | Subsequent Event [Member] | Credit Facility, Revolving Credit Loans [Member]
Subsequent Event [Line Items]
Extinguishment of debt amount			$ 65