BASIS OF PRESENTATION (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 item	Sep. 30, 2012	Dec. 31, 2012	Dec. 31, 2011
Description of Business
Number of acute care hospitals operated by subsidiaries			49
Number of licensed beds in hospitals operated by subsidiaries			13,180
Number of provider-based outpatient centers operated by subsidiaries			134
Minimum number of hospitals to which business process solutions is provided by Conifer			700
Summary of significant accounting policies
Net operating revenues before provision for doubtful accounts	$ 2,618	$ 2,427	$ 7,841	$ 7,373
Gross Carrying Amount	1,213		1,213		1,076
Accumulated Amortization	(490)		(490)		(426)
Net Book Value	723		723		650
Cash Equivalents
Cash and cash equivalents	82	83	82	83	364	113
Book overdrafts classified as accounts payable	182		182		232
Cash and cash equivalents related to captive insurance subsidiaries	51		51		65
Accrued property and equipment purchases for items received but not yet paid			63		98
Accrued property and equipment purchases, for items received but not yet paid, included in accounts payable	50		50		93
Non-cancellable capital leases primarily for equipment			99	54
Capitalized software costs
Summary of significant accounting policies
Gross Carrying Amount	1,048		1,048		927
Accumulated Amortization	(455)		(455)		(399)
Net Book Value	593		593		528
Long-term debt issuance costs
Summary of significant accounting policies
Gross Carrying Amount	107		107		106
Accumulated Amortization	(25)		(25)		(25)
Net Book Value	82		82		81
Other
Summary of significant accounting policies
Gross Carrying Amount	58		58		43
Accumulated Amortization	(10)		(10)		(2)
Net Book Value	48		48		41
Medicare
Summary of significant accounting policies
Net operating revenues before provision for doubtful accounts	501	505	1,543	1,666
Medicaid
Summary of significant accounting policies
Net operating revenues before provision for doubtful accounts	206	176	630	587
Managed care
Summary of significant accounting policies
Net operating revenues before provision for doubtful accounts	1,378	1,348	4,126	4,002
Indemnity, self-pay and other
Summary of significant accounting policies
Net operating revenues before provision for doubtful accounts	262	261	783	747
Acute care hospitals - other revenue
Summary of significant accounting policies
Net operating revenues before provision for doubtful accounts	14	8	53	45
Other operations
Summary of significant accounting policies
Net operating revenues before provision for doubtful accounts	$ 257	$ 129	$ 706	$ 326