Supplemental Condensed Consolidating Financial Information and Other Collateral-Related Information - Schedule of Condensed Consolidating Balance Sheet (Detail) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 705	$ 646	$ 691	$ 741
Accounts receivable, net	5,782	5,826
Inventories	1,544	1,503
Other	1,306	1,111
Total current assets	9,337	9,086
Property and equipment, net	16,768	16,352
Investments of insurance subsidiaries	352	336
Investments in and advances to affiliates	197	206
Goodwill and other intangible assets	6,771	6,704
Other	1,141	1,074
Total assets	34,566	33,758
Current liabilities:
Accounts payable	2,245	2,318
Accrued salaries	1,209	1,265
Other accrued expenses	2,104	2,035
Long-term debt due within one year	213	216
Total current liabilities	5,771	5,834
Long-term debt, net	31,448	31,160
Professional liability risks	1,144	1,148
Income taxes and other liabilities	1,282	1,249
Total liabilities	39,645	39,391
Stockholders' (deficit) equity attributable to HCA Healthcare, Inc.	(6,792)	(7,302)
Noncontrolling interests	1,713	1,669
Total stockholders' deficit	(5,079)	(5,633)
Total liabilities and stockholders' deficit	34,566	33,758
HCA Healthcare, Inc. Issuer [Member]
Current assets:
Investments in and advances to affiliates	28,356	27,045
Other	805	877
Total assets	29,161	27,922
Current liabilities:
Other accrued expenses	281	29
Total current liabilities	281	29
Long-term debt, net	994	993
Intercompany balances	34,258	33,784
Income taxes and other liabilities	420	418
Total liabilities	35,953	35,224
Stockholders' (deficit) equity attributable to HCA Healthcare, Inc.	(6,792)	(7,302)
Total stockholders' deficit	(6,792)	(7,302)
Total liabilities and stockholders' deficit	29,161	27,922
HCA Inc. Issuer [Member]
Current assets:
Other	29
Total assets	29
Current liabilities:
Other accrued expenses	383	572
Long-term debt due within one year	97	97
Total current liabilities	480	669
Long-term debt, net	29,981	29,693
Intercompany balances	(9,404)	(10,277)
Income taxes and other liabilities	5	12
Total liabilities	21,062	20,097
Stockholders' (deficit) equity attributable to HCA Healthcare, Inc.	(21,033)	(20,097)
Total stockholders' deficit	(21,033)	(20,097)
Total liabilities and stockholders' deficit	29
Subsidiary Guarantors [Member]
Current assets:
Cash and cash equivalents	155	110	82	155
Accounts receivable, net	2,991	3,028
Inventories	923	890
Other	522	445
Total current assets	4,591	4,473
Property and equipment, net	8,560	8,463
Investments in and advances to affiliates	15	16
Goodwill and other intangible assets	1,727	1,728
Other	33	34
Total assets	14,926	14,714
Current liabilities:
Accounts payable	1,342	1,439
Accrued salaries	679	704
Other accrued expenses	457	464
Long-term debt due within one year	57	60
Total current liabilities	2,535	2,667
Long-term debt, net	188	199
Intercompany balances	(27,765)	(26,447)
Income taxes and other liabilities	403	387
Total liabilities	(24,639)	(23,194)
Stockholders' (deficit) equity attributable to HCA Healthcare, Inc.	39,438	37,752
Noncontrolling interests	127	156
Total stockholders' deficit	39,565	37,908
Total liabilities and stockholders' deficit	14,926	14,714
Subsidiary Non-Guarantors [Member]
Current assets:
Cash and cash equivalents	550	536	$ 609	$ 586
Accounts receivable, net	2,791	2,798
Inventories	621	613
Other	784	666
Total current assets	4,746	4,613
Property and equipment, net	8,208	7,889
Investments of insurance subsidiaries	352	336
Investments in and advances to affiliates	182	190
Goodwill and other intangible assets	5,044	4,976
Other	274	163
Total assets	18,806	18,167
Current liabilities:
Accounts payable	903	879
Accrued salaries	530	561
Other accrued expenses	983	970
Long-term debt due within one year	59	59
Total current liabilities	2,475	2,469
Long-term debt, net	285	275
Intercompany balances	2,911	2,940
Professional liability risks	1,144	1,148
Income taxes and other liabilities	454	432
Total liabilities	7,269	7,264
Stockholders' (deficit) equity attributable to HCA Healthcare, Inc.	9,951	9,390
Noncontrolling interests	1,586	1,513
Total stockholders' deficit	11,537	10,903
Total liabilities and stockholders' deficit	18,806	18,167
Eliminations [Member]
Current assets:
Investments in and advances to affiliates	(28,356)	(27,045)
Total assets	(28,356)	(27,045)
Current liabilities:
Stockholders' (deficit) equity attributable to HCA Healthcare, Inc.	(28,356)	(27,045)
Total stockholders' deficit	(28,356)	(27,045)
Total liabilities and stockholders' deficit	$ (28,356)	$ (27,045)