Acquisitions and Divestitures (Acqusitions Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		1 Months Ended		1 Months Ended		1 Months Ended		1 Months Ended		1 Months Ended		1 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Jul. 31, 2012 Memorial Health Systems [Member]	Sep. 30, 2012 Memorial Health Systems [Member]	Mar. 31, 2012 Diagnostic Clinic of Longview [Member]	Sep. 30, 2012 Diagnostic Clinic of Longview [Member]	Mar. 31, 2012 Metro South Medical Center [Member]	Sep. 30, 2012 Metro South Medical Center [Member]	Jan. 31, 2012 Moses Taylor Healthcare [Member]	Sep. 30, 2012 Moses Taylor Healthcare [Member]	Oct. 31, 2011 Tomball Regional Hospital [Member]	Sep. 30, 2012 Tomball Regional Hospital [Member]	May 31, 2011 Mercy Health Partners [Member]	Sep. 30, 2012 Mercy Health Partners [Member]	Sep. 30, 2012 Physician Practices Clinics and Other Ancillary Businesses [Member]	Jan. 31, 2012 Moses Taylor Hospital [Member] Moses Taylor Healthcare [Member]	Jan. 31, 2012 Mid-Valley Hospital [Member] Moses Taylor Healthcare [Member]	May 31, 2011 Regional Hospital of Scranton [Member] Mercy Health Partners [Member]	May 31, 2011 Tyler Memorial Hospital [Member] Mercy Health Partners [Member]	May 31, 2011 Special Care Hospital [Member] Mercy Health Partners [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition					Jul. 01, 2012		Mar. 05, 2012		Mar. 01, 2012		Jan. 01, 2012		Oct. 01, 2011		May 01, 2011
Business Acquisition, Number of Licensed Hospital or Facility Beds					100				330				358					217	25	198	48	67
Business Acquisition, Maximum Number of Years for Completion of Replacement Hospital Construction					5 years
Other Commitment					$ 75.0
Business Acquisition, Number of Hospitals Acquired											2				2
Business Acquisition, Cost of Aquired Entity, Cash Paid Including Working Capital							52.3
Business Acquisition, Cost of Acquired Entity, Cash Paid for Fixed Assets					45.0				39.3		151.1		192.0		150.8
Business Acquisition, Cost of Acquired Entity, Cash Paid for Working Capital					2.6				(0.9)		9.2		17.5		(2.1)
Business Acquisition, Cost of Acquired Entity, Cash Paid																	34.6
Business Acquisition, Cost of Acquired Entity, Liabilities Assumed					12.5		6.9		6.2		13.2		15.9		12.3
Business Acquisition, Cost of Acquired Entity, Purchase Price					60.1		59.2		44.6		173.5		225.4		161.0
Business Acquisition, Purchase Price Allocation, Goodwill Amount						9.9		41.8		0		54.6		32.4		43.1	24.4
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment																	9.1
Business Acquisition, Purchase Price Allocation Net Working Capital																	1.1
Business Combination, Acquisition Related Costs	$ 2.5	$ 2.4	$ 9.1	$ 11.0