Earnings Per Share - Schedule of Computations of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Earnings Per Share [Abstract]
Net income attributable to HCA Healthcare, Inc.	$ 5,760	$ 5,242	$ 5,643
Weighted average common shares outstanding	258,603	272,404	290,348
Effect of dilutive incremental shares	3,203	4,008	4,318
Shares used for diluted earnings per share	261,806	276,412	294,666
Basic earnings per share	$ 22.27	$ 19.25	$ 19.43
Diluted earnings per share	$ 22	$ 18.97	$ 19.15