Consolidated Income Statements - USD ($) shares in Thousands, $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenues	$ 13,523	$ 12,694	$ 12,602	$ 12,517	$ 12,274	$ 11,451	$ 11,529	$ 11,423	$ 51,336	$ 46,677	$ 43,614
Salaries and benefits									23,560	21,425	20,059
Supplies									8,481	7,724	7,316
Other operating expenses									9,481	8,608	8,051
Equity in earnings of affiliates									(43)	(29)	(45)
Depreciation and amortization									2,596	2,278	2,131
Interest expense									1,824	1,755	1,690
Gains on sales of facilities									(18)	(428)	(8)
Losses on retirement of debt									211	9	39
Total expenses including equity in earnings of affiliates									46,092	41,342	39,233
Income before income taxes									5,244	5,335	4,381
Provision for income taxes									1,099	946	1,638
Net income	1,273	764	927	1,181	1,245	896	966	1,282	4,145	4,389	2,743
Net income attributable to noncontrolling interests									640	602	527
Net income attributable to HCA Healthcare, Inc.	$ 1,071	$ 612	$ 783	$ 1,039	$ 1,064	$ 759	$ 820	$ 1,144	$ 3,505	$ 3,787	$ 2,216
Per share data:
Basic earnings	$ 3.16	$ 1.80	$ 2.29	$ 3.03	$ 3.09	$ 2.20	$ 2.35	$ 3.26	$ 10.27	$ 10.90	$ 6.12
Diluted earnings	$ 3.09	$ 1.76	$ 2.25	$ 2.97	$ 3.01	$ 2.15	$ 2.31	$ 3.18	$ 10.07	$ 10.66	$ 5.95
Shares used in earnings per share calculations (in millions):
Basic									341,210	347,297	362,305
Diluted									348,226	355,303	372,221