Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill Gross, Balance, beginning period	$ 7,373	$ 7,537
Accumulated impairment losses, Balance, beginning of period	(2,814)	(2,814)
Goodwill, Balance, beginning of period	4,559	4,723
Goodwill acquired as part of acquisitions during current year	4	22
Goodwill allocated to hospitals held for sale	(235)	(186)
Goodwill Gross, Balance, end of period	7,142	7,373
Accumulated impairment losses, Balance, end of period	(2,814)	(2,814)
Goodwill, Balance, end of year	$ 4,328	$ 4,559