Income Taxes - Schedule of Reconciliation of Federal Statutory Rate to Effective Income Tax Rate (Detail)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	21.00%	21.00%
State income taxes, net of federal tax benefit	2.70%	2.60%	2.30%
Change in liability for uncertain tax positions	(2.30%)	0.40%	0.70%
Tax benefit from settlements of employee equity awards	(1.20%)	(1.20%)	(0.90%)
Internal restructuring of affiliates	3.50%	0.00%	0.00%
Other items, net	0.80%	0.80%	0.50%
Effective income tax rate on income attributable to HCA Healthcare, Inc.	24.50%	23.60%	23.60%
Income attributable to noncontrolling interests from consolidated partnerships	(2.60%)	(2.60%)	(3.30%)
Effective income tax rate on income before income taxes	21.90%	21.00%	20.30%