Supplemental Condensed Consolidating Financial Information - Schedule of Condensed Consolidating Statement of Cash Flows (Detail) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Cash flows from operating activities:
Net income (loss)	$ 1,697	$ 1,442
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Changes in operating assets and liabilities	(2,945)	(3,319)
Provision for doubtful accounts	2,337	2,732
Depreciation and amortization	1,361	1,292
Income taxes	(61)	158
Losses (gains) on sales of facilities	(20)	13
Losses on retirement of debt	226	17
Legal claim costs	78
Amortization of deferred loan costs	33	41
Share-based compensation	118	81
Equity in earnings of affiliates
Other	(3)	(3)
Net cash provided by operating activities	2,821	2,454
Cash flows from investing activities:
Purchase of property and equipment	(1,482)	(1,347)
Acquisition of hospitals and health care entities	(97)	(463)
Disposition of hospitals and health care entities	38	31
Change in investments	22	97
Other	7	8
Net cash used in investing activities	(1,512)	(1,674)
Cash flows from financing activities:
Issuance of long-term debt	3,502
Net change in revolving credit facilities	(160)	630
Repayment of long-term debt	(3,525)	(1,300)
Distributions to noncontrolling interests	(325)	(308)
Payment of debt issuance costs	(49)	(5)
Repurchase of common stock	(750)
Distributions to stockholders	(7)	(13)
Changes in intercompany balances with affiliates, net
Income tax benefits	119	70
Other	(13)	(75)
Net cash used in financing activities	(1,208)	(1,001)
Change in cash and cash equivalents	101	(221)
Cash and cash equivalents at beginning of period	414	705
Cash and cash equivalents at end of period	515	484
HCA Holdings, Inc. Issuer [Member]
Cash flows from operating activities:
Net income (loss)	1,399	1,215
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Changes in operating assets and liabilities	18	47
Provision for doubtful accounts
Depreciation and amortization
Income taxes	(61)	158
Losses (gains) on sales of facilities
Losses on retirement of debt
Legal claim costs
Amortization of deferred loan costs	2	3
Share-based compensation	118	81
Equity in earnings of affiliates	(1,494)	(1,303)
Other
Net cash provided by operating activities	(18)	201
Cash flows from investing activities:
Purchase of property and equipment
Acquisition of hospitals and health care entities
Disposition of hospitals and health care entities
Change in investments
Other
Net cash used in investing activities
Cash flows from financing activities:
Issuance of long-term debt
Net change in revolving credit facilities
Repayment of long-term debt
Distributions to noncontrolling interests
Payment of debt issuance costs
Repurchase of common stock	(750)
Distributions to stockholders	(7)	(13)
Changes in intercompany balances with affiliates, net	654	(199)
Income tax benefits	119	70
Other	2	(81)
Net cash used in financing activities	18	(223)
Change in cash and cash equivalents		(22)
Cash and cash equivalents at beginning of period		22
Cash and cash equivalents at end of period
HCA Inc. Issuer [Member]
Cash flows from operating activities:
Net income (loss)	(1,204)	(1,028)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Changes in operating assets and liabilities	(151)	(126)
Provision for doubtful accounts
Depreciation and amortization
Income taxes
Losses (gains) on sales of facilities
Losses on retirement of debt	226	17
Legal claim costs	78
Amortization of deferred loan costs	31	38
Share-based compensation
Equity in earnings of affiliates
Other	3	7
Net cash provided by operating activities	(1,017)	(1,092)
Cash flows from investing activities:
Purchase of property and equipment
Acquisition of hospitals and health care entities
Disposition of hospitals and health care entities
Change in investments
Other
Net cash used in investing activities
Cash flows from financing activities:
Issuance of long-term debt	3,502
Net change in revolving credit facilities	(160)	630
Repayment of long-term debt	(3,462)	(1,243)
Distributions to noncontrolling interests
Payment of debt issuance costs	(49)	(5)
Repurchase of common stock
Distributions to stockholders
Changes in intercompany balances with affiliates, net	1,186	1,710
Income tax benefits
Other
Net cash used in financing activities	1,017	1,092
Change in cash and cash equivalents
Cash and cash equivalents at beginning of period
Cash and cash equivalents at end of period
Subsidiary Guarantors [Member]
Cash flows from operating activities:
Net income (loss)	1,880	1,665
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Changes in operating assets and liabilities	(1,660)	(1,848)
Provision for doubtful accounts	1,388	1,611
Depreciation and amortization	667	636
Income taxes
Losses (gains) on sales of facilities	(16)	20
Losses on retirement of debt
Legal claim costs
Amortization of deferred loan costs
Share-based compensation
Equity in earnings of affiliates
Other
Net cash provided by operating activities	2,259	2,084
Cash flows from investing activities:
Purchase of property and equipment	(893)	(684)
Acquisition of hospitals and health care entities	(7)
Disposition of hospitals and health care entities	31	17
Change in investments	22	(6)
Other
Net cash used in investing activities	(847)	(673)
Cash flows from financing activities:
Issuance of long-term debt
Net change in revolving credit facilities
Repayment of long-term debt	(35)	(34)
Distributions to noncontrolling interests	(45)	(34)
Payment of debt issuance costs
Repurchase of common stock
Distributions to stockholders
Changes in intercompany balances with affiliates, net	(1,331)	(1,559)
Income tax benefits
Other
Net cash used in financing activities	(1,411)	(1,627)
Change in cash and cash equivalents	1	(216)
Cash and cash equivalents at beginning of period	112	383
Cash and cash equivalents at end of period	113	167
Subsidiary Non-Guarantors [Member]
Cash flows from operating activities:
Net income (loss)	1,116	893
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Changes in operating assets and liabilities	(1,152)	(1,392)
Provision for doubtful accounts	949	1,121
Depreciation and amortization	694	656
Income taxes
Losses (gains) on sales of facilities	(4)	(7)
Losses on retirement of debt
Legal claim costs
Amortization of deferred loan costs
Share-based compensation
Equity in earnings of affiliates
Other	(6)	(10)
Net cash provided by operating activities	1,597	1,261
Cash flows from investing activities:
Purchase of property and equipment	(589)	(663)
Acquisition of hospitals and health care entities	(90)	(463)
Disposition of hospitals and health care entities	7	14
Change in investments		103
Other	7	8
Net cash used in investing activities	(665)	(1,001)
Cash flows from financing activities:
Issuance of long-term debt
Net change in revolving credit facilities
Repayment of long-term debt	(28)	(23)
Distributions to noncontrolling interests	(280)	(274)
Payment of debt issuance costs
Repurchase of common stock
Distributions to stockholders
Changes in intercompany balances with affiliates, net	(509)	48
Income tax benefits
Other	(15)	6
Net cash used in financing activities	(832)	(243)
Change in cash and cash equivalents	100	17
Cash and cash equivalents at beginning of period	302	300
Cash and cash equivalents at end of period	402	317
Eliminations [Member]
Cash flows from operating activities:
Net income (loss)	(1,494)	(1,303)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Changes in operating assets and liabilities
Provision for doubtful accounts
Depreciation and amortization
Income taxes
Losses (gains) on sales of facilities
Losses on retirement of debt
Legal claim costs
Amortization of deferred loan costs
Share-based compensation
Equity in earnings of affiliates	1,494	1,303
Other
Net cash provided by operating activities
Cash flows from investing activities:
Purchase of property and equipment
Acquisition of hospitals and health care entities
Disposition of hospitals and health care entities
Change in investments
Other
Net cash used in investing activities
Cash flows from financing activities:
Issuance of long-term debt
Net change in revolving credit facilities
Repayment of long-term debt
Distributions to noncontrolling interests
Payment of debt issuance costs
Repurchase of common stock
Distributions to stockholders
Changes in intercompany balances with affiliates, net
Income tax benefits
Other
Net cash used in financing activities
Change in cash and cash equivalents
Cash and cash equivalents at beginning of period
Cash and cash equivalents at end of period