Supplemental Condensed Consolidating Financial Information and Other Collateral-Related Information - Schedule of Consolidated Statements of Stockholder's Deficit and Consolidated Statement of Cash Flows (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Presentation in HCA Healthcare, Inc. Consolidated Statements of Stockholders' Deficit:
Repurchases of common stock	$ (1,530)	$ (2,051)	$ (2,751)
Cash dividends declared ($1.40 per share)	(496)
Other	12	10	(6)
Presentation in HCA Healthcare, Inc. Consolidated Statements of Cash Flows (cash flows from financing activities):
Repurchases of common stock	(1,530)	(2,051)	(2,751)
Payment of cash dividends	(487)
Healthtrust, Inc. [Member]
Presentation in HCA Healthcare, Inc. Consolidated Statements of Stockholders' Deficit:
Repurchases of common stock	(1,530)	(2,051)	(2,751)
Share-based benefit plans	115	281	233
Cash dividends declared ($1.40 per share)	(496)
Other	(12)	(10)	(2)
Distributions to HCA Healthcare, Inc., net of contributions from HCA Healthcare, Inc.	(1,923)	(1,780)	(2,520)
Presentation in HCA Healthcare, Inc. Consolidated Statements of Cash Flows (cash flows from financing activities):
Repurchases of common stock	(1,530)	(2,051)	(2,751)
Payment of cash dividends	(487)
Cash distributions to HCA Healthcare, Inc.	$ (2,017)	$ (2,051)	$ (2,751)