Segment Information (Schedule of Segment Reporting Information by Segment) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Segment Reporting Information [Line Items]
Net operating revenues	$ 4,911	$ 4,176
Income (loss) from continuing operations before income taxes	168	(132)
Hospital operations [Member]
Segment Reporting Information [Line Items]
Net operating revenues	4,857	4,124
Income (loss) from continuing operations before income taxes	273	38
Corporate and All Other Reporting Units [Member]
Segment Reporting Information [Line Items]
Net operating revenues	54	52
Income (loss) from continuing operations before income taxes	$ (105)	$ (170)