Consolidated Comprehensive Income Statements - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 4,389	$ 2,743	$ 3,432
Other comprehensive income (loss) before taxes:
Foreign currency translation	(71)	97	(224)
Unrealized gains (losses) on available-for-salesecurities	(7)	1	(9)
Realized gains included in other operating expenses		(2)
Total unrealized gains (losses) on available-for-sale securities	(7)	(1)	(9)
Defined benefit plans	44	(43)	(35)
Pension costs included in salaries and benefits	21	18	18
Total defined benefit plans	65	(25)	(17)
Change in fair value of derivative financial instruments	23	11	20
Interest (benefits) costs included in interest expense	(10)	20	109
Total change in fair value of derivative financial instruments	13	31	129
Other comprehensive income (loss) before taxes		102	(121)
Income taxes (benefits) related to other comprehensive income items	8	42	(48)
Other comprehensive income (loss)	(8)	60	(73)
Comprehensive income	4,381	2,803	3,359
Comprehensive income attributable to noncontrolling interests	602	527	542
Comprehensive income attributable to HCA Healthcare, Inc.	$ 3,779	$ 2,276	$ 2,817