Goodwill and Other Intangible Assets (Goodwill Narrative) (Details) - USD ($) $ in Millions	6 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2016	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Goodwill			$ 4,723	$ 6,521	$ 8,965
Goodwill, Impairment Loss	$ 1,400	$ 1,395	$ 1,419	1,395
Goodwill allocated to QHC in the spin-off				709
Hospital Operations [Member]
Goodwill [Line Items]
Goodwill				6,500
Goodwill allocated to QHC in the spin-off				676
Home Care Agency Operations Reporting Unit [Member]
Goodwill [Line Items]
Goodwill				46
Hospital Management Services Reporting Unit [Member]
Goodwill [Line Items]
Goodwill allocated to QHC in the spin-off				$ 33