Supplemental Condensed Consolidating Financial Information - Schedule of Condensed Consolidating Comprehensive Income Statement (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended					9 Months Ended
	Sep. 30, 2014	Mar. 31, 2014	Sep. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013
Supplemental Condensed Consolidating Financial Information [Line Items]
Revenues before provision for doubtful accounts	$ 9,978		$ 9,411			$ 29,619	$ 28,078
Provision for doubtful accounts	758		955			2,337	2,732
Revenues	9,220		8,456			27,282	25,346
Salaries and benefits	4,211		3,916			12,359	11,681
Supplies	1,539		1,457			4,603	4,406
Other operating expenses	1,688		1,564			4,977	4,594
Electronic health record incentive income	(32)		(75)			(97)	(166)
Equity in earnings of affiliates	(14)		(9)			(32)	(29)
Depreciation and amortization	460		443			1,361	1,292
Interest expense	427		458			1,314	1,392
Losses (gains) on sales of facilities	12		1			(20)	13
Losses on retirement of debt				17		226	17
Legal claim costs		78			175	78
Management fees
Total expenses including equity in earnings of affiliates	8,291		7,755			24,769	23,200
Income (loss) before income taxes	929		701			2,513	2,146
Provision (benefit) for income taxes	318		234			816	704
Net income (loss)	611		467			1,697	1,442
Net income attributable to noncontrolling interests	93		102			349	310
Net income (loss) attributable to HCA Holdings, Inc.	518		365			1,348	1,132
Comprehensive income (loss) attributable to HCA Holdings, Inc.	511		417			1,399	1,215
HCA Holdings, Inc. Issuer [Member]
Supplemental Condensed Consolidating Financial Information [Line Items]
Revenues before provision for doubtful accounts
Provision for doubtful accounts
Revenues
Salaries and benefits
Supplies
Other operating expenses	4		2			14	4
Electronic health record incentive income
Equity in earnings of affiliates	(542)		(443)			(1,494)	(1,303)
Depreciation and amortization
Interest expense	46		41			138	138
Losses (gains) on sales of facilities
Losses on retirement of debt
Legal claim costs
Management fees
Total expenses including equity in earnings of affiliates	(492)		(400)			(1,342)	(1,161)
Income (loss) before income taxes	492		400			1,342	1,161
Provision (benefit) for income taxes	(19)		(17)			(57)	(54)
Net income (loss)	511		417			1,399	1,215
Net income attributable to noncontrolling interests
Net income (loss) attributable to HCA Holdings, Inc.	511		417			1,399	1,215
Comprehensive income (loss) attributable to HCA Holdings, Inc.	511		417			1,399	1,215
HCA Inc. Issuer [Member]
Supplemental Condensed Consolidating Financial Information [Line Items]
Revenues before provision for doubtful accounts
Provision for doubtful accounts
Revenues
Salaries and benefits
Supplies
Other operating expenses			(1)				(1)
Electronic health record incentive income
Equity in earnings of affiliates
Depreciation and amortization
Interest expense	536		549			1,629	1,651
Losses (gains) on sales of facilities
Losses on retirement of debt						226	17
Legal claim costs						78
Management fees
Total expenses including equity in earnings of affiliates	536		548			1,933	1,667
Income (loss) before income taxes	(536)		(548)			(1,933)	(1,667)
Provision (benefit) for income taxes	(205)		(214)			(729)	(639)
Net income (loss)	(331)		(334)			(1,204)	(1,028)
Net income attributable to noncontrolling interests
Net income (loss) attributable to HCA Holdings, Inc.	(331)		(334)			(1,204)	(1,028)
Comprehensive income (loss) attributable to HCA Holdings, Inc.	(303)		(331)			(1,154)	(961)
Subsidiary Guarantors [Member]
Supplemental Condensed Consolidating Financial Information [Line Items]
Revenues before provision for doubtful accounts	5,133		4,945			15,242	14,829
Provision for doubtful accounts	457		560			1,388	1,611
Revenues	4,676		4,385			13,854	13,218
Salaries and benefits	2,176		2,090			6,393	6,275
Supplies	797		773			2,416	2,340
Other operating expenses	804		771			2,366	2,260
Electronic health record incentive income	(22)		(53)			(68)	(115)
Equity in earnings of affiliates	(3)					(5)	(2)
Depreciation and amortization	225		216			667	636
Interest expense	(115)		(104)			(349)	(319)
Losses (gains) on sales of facilities	16		1			(16)	20
Losses on retirement of debt
Legal claim costs
Management fees	(178)		(183)			(528)	(547)
Total expenses including equity in earnings of affiliates	3,700		3,511			10,876	10,548
Income (loss) before income taxes	976		874			2,978	2,670
Provision (benefit) for income taxes	365		334			1,098	1,005
Net income (loss)	611		540			1,880	1,665
Net income attributable to noncontrolling interests	18		19			65	48
Net income (loss) attributable to HCA Holdings, Inc.	593		521			1,815	1,617
Comprehensive income (loss) attributable to HCA Holdings, Inc.	595		532			1,822	1,637
Subsidiary Non-Guarantors [Member]
Supplemental Condensed Consolidating Financial Information [Line Items]
Revenues before provision for doubtful accounts	4,845		4,466			14,377	13,249
Provision for doubtful accounts	301		395			949	1,121
Revenues	4,544		4,071			13,428	12,128
Salaries and benefits	2,035		1,826			5,966	5,406
Supplies	742		684			2,187	2,066
Other operating expenses	880		792			2,597	2,331
Electronic health record incentive income	(10)		(22)			(29)	(51)
Equity in earnings of affiliates	(11)		(9)			(27)	(27)
Depreciation and amortization	235		227			694	656
Interest expense	(40)		(28)			(104)	(78)
Losses (gains) on sales of facilities	(4)					(4)	(7)
Losses on retirement of debt
Legal claim costs
Management fees	178		183			528	547
Total expenses including equity in earnings of affiliates	4,005		3,653			11,808	10,843
Income (loss) before income taxes	539		418			1,620	1,285
Provision (benefit) for income taxes	177		131			504	392
Net income (loss)	362		287			1,116	893
Net income attributable to noncontrolling interests	75		83			284	262
Net income (loss) attributable to HCA Holdings, Inc.	287		204			832	631
Comprehensive income (loss) attributable to HCA Holdings, Inc.	250		242			826	627
Eliminations [Member]
Supplemental Condensed Consolidating Financial Information [Line Items]
Revenues before provision for doubtful accounts
Provision for doubtful accounts
Revenues
Salaries and benefits
Supplies
Other operating expenses
Electronic health record incentive income
Equity in earnings of affiliates	542		443			1,494	1,303
Depreciation and amortization
Interest expense
Losses (gains) on sales of facilities
Losses on retirement of debt
Legal claim costs
Management fees
Total expenses including equity in earnings of affiliates	542		443			1,494	1,303
Income (loss) before income taxes	(542)		(443)			(1,494)	(1,303)
Provision (benefit) for income taxes
Net income (loss)	(542)		(443)			(1,494)	(1,303)
Net income attributable to noncontrolling interests
Net income (loss) attributable to HCA Holdings, Inc.	(542)		(443)			(1,494)	(1,303)
Comprehensive income (loss) attributable to HCA Holdings, Inc.	$ (542)		$ (443)			$ (1,494)	$ (1,303)