Condensed Consolidated Comprehensive Income Statements (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 530	$ 745	$ 2,102	$ 2,347
Other comprehensive income (loss) before taxes:
Foreign currency translation	32	(40)	87	(169)
Unrealized gains (losses) on available-for-sale securities		(2)	5	3
Defined benefit plans	0	0	0	0
Pension costs included in salaries and benefits	5	4	14	13
Total defined benefit plans	5	4	14	13
Change in fair value of derivative financial instruments	(1)	13	(9)	(57)
Interest costs included in interest expense	4	28	17	84
Total change in fair value of derivative financial instruments	3	41	8	27
Other comprehensive income (loss) before taxes	40	3	114	(126)
Income taxes (benefits) related to other comprehensive income items	15		44	(50)
Other comprehensive income (loss)	25	3	70	(76)
Comprehensive income	555	748	2,172	2,271
Comprehensive income attributable to noncontrolling interests	104	127	360	377
Comprehensive income attributable to HCA Healthcare, Inc.	$ 451	$ 621	$ 1,812	$ 1,894