Accounting Policies - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	1 Months Ended		12 Months Ended
	Mar. 31, 2011	Jan. 01, 2000	Dec. 31, 2012 D State	Dec. 31, 2011 D	Dec. 31, 2010 D
Summary Of Significant Accounting Policies [Line Items]
Initial public offering of shares common stock	87,719,300
Initial public offering of shares of common stock, price per share	$ 30.00
Number of owned and operated hospitals			162
Number of freestanding surgery centers			112
Number of facilities locations			20
General and administrative expense			$ 248	$ 228	$ 182
Adjustments to estimated reimbursement filed during respective year			50	40	52
Adjustments to estimated reimbursement filed during previous years			242	30	50
Adjustments to Medicare revenues			196
Revenue related to operations in previous year			46
Percentage of income of federal poverty level eligible for charity care			200.00%
Percentage of the sum of revenues, uninsured discounts and charity care			29.50%	27.40%	25.60%
Outstanding checks unpresented for payment			437	382
Allowance for doubtful accounts percentage of accounts receivable			93.00%	92.00%
Allowance for doubtful accounts			5,228	4,478
Days revenues in accounts receivable			52	53	50
Depreciation expense			1,673	1,461	1,416
Goodwill impairments		102	0	0	14
Goodwill increased related to acquisitions			288	2,329
Goodwill decrease related to facility sales			3	24
Goodwill decrease related to foreign currency translation and other adjustments			3	16
Other intangible assets			0	269	0
Deferred loan costs			571	638
Deferred loan costs, accumulated amortization			281	348
Amortization of deferred loan costs			62	70	81
Physician recruiting liability amounts			15	15
Maximum amount pay under effective minimum revenue guarantees			37
Reserves for professional liability risks			1,297	1,291
Current portion of professional liability risks reserves			324	298
Provisions for losses related to professional liability risks			331	244	222
Reserves for professional liability risks cover individual claims			2,700	2,700
Net payments of professional and general liability claims			335	240
Self-insured retention amount per occurrence			5
Maximum amount losses per occurrence			50
Reinsurance for professional liability risks retention level of amount per occurrence			15
Amounts receivable under reinsurance contracts recorded in other assets			17	25
Amounts receivable under reinsurance contracts recorded in other current assets			32	14
Electronic health record incentive income			336	210
Incentive income, Medicaid			89	87
Incentive income, Medicare			247	123
Electronic health record deferred incentive income			113	134
Investor final fee upon completion of initial public offering of common stock	181
Percentage of fee				1.00%
Investors fee related to the initial public offering of common stock, recorded as cost of stock offering				26
Annual management fee					18
Rural Floor Provision Settlement Effect [Member]
Summary Of Significant Accounting Policies [Line Items]
Adjustments to Medicare revenues			271
Implementation of Revised Supplemental Security Income Ratios [Member]
Summary Of Significant Accounting Policies [Line Items]
Adjustments to Medicare revenues			$ 75
Minimum [Member] | Building and improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives in years			10 years
Minimum [Member] | Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives in years			4 years
Maximum [Member] | Building and improvements [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives in years			40 years
Maximum [Member] | Equipment [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives in years			10 years