Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended			180 Months Ended	0 Months Ended
	Dec. 31, 2014 Hospital Claim State Surgery_Center Claims	Dec. 31, 2013 Claims	Dec. 31, 2012	Dec. 31, 2014 Hospital Claim State Surgery_Center	Jan. 01, 2015
Summary Of Significant Accounting Policies [Line Items]
Number of owned and operated hospitals	166			166
Number of freestanding surgery centers	113			113
Number of facilities locations	20			20
General and administrative expense	$ 285,000,000	$ 287,000,000	$ 248,000,000
Adjustments to estimated reimbursement filed during respective year	50,000,000	41,000,000	50,000,000
Adjustments to estimated reimbursement filed during previous years	53,000,000	68,000,000	242,000,000
Revenue related to operations in previous year			46,000,000
Percentage of the sum of revenues, uninsured discounts and charity care	30.20%	31.30%	29.50%
Outstanding checks unpresented for payment	511,000,000	461,000,000		511,000,000
Allowance for doubtful accounts percentage of accounts receivable	91.40%	92.60%
Allowance for doubtful accounts	5,482,000,000	5,927,000,000		5,482,000,000
Days revenues in accounts receivable	54 days	54 days	51 days
Depreciation expense	1,798,000,000	1,733,000,000	1,673,000,000
Goodwill impairments	0	0	0	102,000,000
Intangible assets increased	6,000,000	125,000,000		6,000,000
Intangible assets decreased	22,000,000	12,000,000
Gross carrying amount of intangible assets	162,000,000	162,000,000
Accumulated amortization of intangible assets	38,000,000	16,000,000		38,000,000
Gross carrying amount of indefinite-lived intangible assets	275,000,000	269,000,000		275,000,000
Deferred loan costs	375,000,000	542,000,000		375,000,000
Deferred loan costs, accumulated amortization	156,000,000	305,000,000		156,000,000
Amortization of deferred loan costs	42,000,000	55,000,000	62,000,000
Physician recruiting liability amounts	14,000,000	15,000,000		14,000,000
Maximum amount pay under effective minimum revenue guarantees	44,000,000			44,000,000
Reserves for professional liability risks	1,407,000,000	1,279,000,000		1,407,000,000
Current portion of professional liability risks reserves	329,000,000	330,000,000		329,000,000
Provisions for losses related to professional liability risks	395,000,000	314,000,000	331,000,000
Reserves for professional liability risks cover individual claims	2,700	2,600		2,700
Net payments of professional and general liability claims	268,000,000	307,000,000
Insurance subsidiary ownership percentage	100.00%			100.00%
Self-insured retention amount per occurrence	5,000,000
Maximum amount losses per occurrence	50,000,000
Reinsurance for professional liability risks retention level of amount per occurrence	15,000,000
Amounts receivable under reinsurance contracts recorded in other assets	20,000,000	19,000,000		20,000,000
Amounts receivable under reinsurance contracts recorded in other current assets	5,000,000	5,000,000		5,000,000
Electronic health record incentive income	125,000,000	216,000,000	336,000,000
Incentive income, Medicaid	7,000,000	33,000,000	84,000,000
Incentive income, Medicare	118,000,000	183,000,000	252,000,000
Electronic health record deferred incentive income	39,000,000	78,000,000		39,000,000
Rural Floor Provision Settlement Effect [Member]
Summary Of Significant Accounting Policies [Line Items]
Adjustments to Medicare revenues	271,000,000
Implementation of Revised Supplemental Security Income Ratios [Member]
Summary Of Significant Accounting Policies [Line Items]
Adjustments to Medicare revenues	75,000,000
Subsequent Event [Member]
Summary Of Significant Accounting Policies [Line Items]
Self-insured retention amount per occurrence					15,000,000
Acquisitions [Member]
Summary Of Significant Accounting Policies [Line Items]
Goodwill increase (decrease)	542,000,000	253,000,000
Foreign Currency Translation And Other [Member]
Summary Of Significant Accounting Policies [Line Items]
Goodwill increase (decrease)	$ (13,000,000)	$ (2,000,000)
Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Percentage of income of federal poverty level eligible for charity care	200.00%
Finite lived intangible asset useful life	10 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
Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Finite lived intangible asset useful life	3 years
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