Consolidated Comprehensive Income Statements - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 4,387	$ 4,145	$ 4,389
Other comprehensive income (loss) before taxes:
Foreign currency translation	18	5	(71)
Unrealized gains (losses) on available-for-sale securities	14	15	(7)
Defined benefit plans	(71)	(63)	44
Pension costs included in salaries and benefits	28	13	21
Total defined benefit plans	(43)	(50)	65
Change in fair value of derivative financial instruments	(66)	(50)	23
Interest costs (benefits) included in interest expense	24	(17)	(10)
Total change in fair value of derivative financial instruments	(42)	(67)	13
Other comprehensive loss before taxes	(53)	(97)	0
Income taxes (benefits) related to other comprehensive income items	(11)	(18)	8
Other comprehensive loss	(42)	(79)	(8)
Comprehensive income	4,345	4,066	4,381
Comprehensive income attributable to noncontrolling interests	633	640	602
Comprehensive income attributable to HCA Healthcare, Inc.	$ 3,712	$ 3,426	$ 3,779