Share Repurchase Transactions and Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss (Parenthetical) (Detail) $ in Millions	3 Months Ended
Mar. 31, 2025 USD ($)
Equity [Abstract]
Unrealized losses on available-for-sale securities, net of income taxes	$ 2
Foreign currency translation adjustments, net of income taxes	$ 4

Other comprehensive income unrealized holding loss on debt securities arising during period tax benefit.

No definition available.

Name:	hca_OtherComprehensiveIncomeUnrealizedHoldingLossOnDebtSecuritiesArisingDuringPeriodTaxBenefit
Namespace Prefix:	hca_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration