Earnings Per Share - Schedule of Computations of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Earnings Per Share [Abstract]
Net income attributable to HCA Healthcare, Inc.	$ 1,461	$ 1,193	$ 3,052	$ 2,556
Weighted average common shares outstanding	261,156	274,494	262,795	275,695
Effect of dilutive incremental shares	2,915	3,704	3,249	3,878
Shares used for diluted earnings per share	264,071	278,198	266,044	279,573
Basic earnings per share	$ 5.6	$ 4.35	$ 11.61	$ 9.27
Diluted earnings per share	$ 5.53	$ 4.29	$ 11.47	$ 9.14