Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($)
Goodwill [Roll Forward]
Goodwill Gross, Balance, beginning period	$ 7,142
Accumulated impairment losses, Balance, beginning of period	(2,814)
Goodwill, Balance, beginning of period	4,328
Goodwill allocated to hospitals held for sale	(6)
Goodwill allocated to hospitals held for sale	(6)
Goodwill Gross, Balance, end of period	7,136
Accumulated impairment losses, Balance, end of period	(2,814)
Goodwill, Balance, end of year	$ 4,322