Commitments and Contingencies (Narrative) (Details) $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($)
Physician Recruiting Commitments [Abstract]
Physician recruiting commitment, physician income guarantee period	12 months
Physician recruiting commitment, period of recoverability of physician income guarantee for noncommitment	3 years
Physician recruiting commitment, maximum potential future payments in excess of liability recorded	$ 34
York, Pennsylvania hospital [Member]
Construction and Other Capital Commitments [Abstract]
Capital commitment, post-acquisition estimated cost of replacement hospital	125
Capital commitment, construction cost of replacement hospital incurred to date	5
All other purchase commitments [Member]
Construction and Other Capital Commitments [Abstract]
Capital commitment, post-acquisition estimated cost of replacement hospital	516
Capital commitment, construction cost of replacement hospital incurred to date	$ 254
Minimum [Member] | All other purchase commitments [Member]
Construction and Other Capital Commitments [Abstract]
Capital commitment, future period after acquisition for completing open capital improvement projects	5 years
Maximum [Member] | All other purchase commitments [Member]
Construction and Other Capital Commitments [Abstract]
Capital commitment, future period after acquisition for completing open capital improvement projects	7 years