Acquisitions and Divestitures (Acquisitions Narrative) (Details) (USD $)	3 Months Ended		0 Months Ended			1 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Nov. 03, 2014	Oct. 01, 2014	Apr. 01, 2014	Jan. 27, 2014 item state	Dec. 31, 2014
Business Acquisition [Line Items]
Business Combination, Acquisition Related Costs	$ 3,000,000	$ 57,000,000
Business Acquisition, Purchase Price Allocation, Goodwill	8,954,000,000						8,951,000,000
Business Combination Contingent Consideration Arrangements, Contingent Value Right, Amount Per Share	$ 1.00
Senior Secured Notes at 5.125, Due 2021 [Member] | Senior Secured Notes [Member]
Business Acquisition [Line Items]
Debt Instrument, Face Amount						1,000,000,000
Debt Instrument, Interest Rate, Stated Percentage						5.125%
Senior Notes at 6.875, Due 2022 [Member] | Senior Notes [Member]
Business Acquisition [Line Items]
Debt Instrument, Face Amount						3,000,000,000
Debt Instrument, Interest Rate, Stated Percentage						6.875%
Lake Norman [Member]
Business Acquisition [Line Items]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Changes, Purchase of Interest by Parent			150,000,000
Business Acquisition, Percentage of Voting Interests Acquired			30.00%
Upstate Carolina Medical Center [Member]
Business Acquisition [Line Items]
Business Acquisition, Number of Licensed Hospital or Facility Beds			125
Business Acquisition, Cost of Acquired Entity, Purchase Price			4,000,000
Business Acquisition, Purchase Price Allocation, Goodwill	0
Novant [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Nov. 03, 2014
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities			5,000,000
Natchez Regional Medical Center [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Oct. 01, 2014
Business Acquisition, Number of Licensed Hospital or Facility Beds				179
Business Acquisition, Cost of Acquired Entity, Purchase Price				10,000,000
Prepayment of future property taxes				8,000,000
Period of prepayment for future property taxes will be applied to the tax liability				17 years
Business Acquisition, Purchase Price Allocation, Goodwill	0
Sharon Regional Health System [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Apr. 01, 2014
Business Acquisition, Number of Licensed Hospital or Facility Beds					258
Business Acquisition, Cost of Acquired Entity, Cash Paid for Fixed Assets					67,000,000
Business Acquisition, Cost of Acquired Entity, Cash Paid for Working Capital					1,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities					9,000,000
Business Acquisition, Cost of Acquired Entity, Purchase Price					77,000,000
Business Acquisition, Purchase Price Allocation, Goodwill	8,000,000
Munroe Regional Medical Center [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Apr. 01, 2014
Business Acquisition, Number of Licensed Hospital or Facility Beds					421
Business Acquisition, Cost of Acquired Entity, Cash Paid for Fixed Assets					192,000,000
Business Acquisition, Cost of Acquired Entity, Cash Paid for Working Capital					4,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities					11,000,000
Business Acquisition, Cost of Acquired Entity, Purchase Price					207,000,000
Business Acquisition, Purchase Price Allocation, Goodwill	11,000,000
Business Acquisition, Percentage of Voting Interests Acquired					95.00%
Business Combination, Assumed Noncontrolling Interest, Fair Value					10,000,000
Munroe Regional Medical Center [Member] | Affiliate of Regional Not-for-Profit Healthcare System [Member]
Business Acquisition [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners					5.00%
Health Management Associates, Inc. [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition	Jan. 27, 2014
Business Acquisition, Purchase Price Allocation, Goodwill							4,500,000,000
Business Combination Consideration Transferred And Existing Indebtedness Assumed						7,300,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt						3,800,000,000
Payments to Acquire Businesses, Gross, Per Share						$ 10.50
Business Combination Consideration Transferred Equity Interests Issued, Per Share						0.06942
Business Combination Contingent Consideration Arrangements, Contingent Value Right, Number Per Share						1
Business Combination Contingent Consideration Arrangements, Contingent Value Right, Amount Per Share						$ 1.00
Business Acquisition, Number of Hospitals Acquired						71
Number of States in which Entity Operates						15
Physician Practices Clinics and Other Ancillary Businesses [Member]
Business Acquisition [Line Items]
Business Acquisition, Cost of Acquired Entity, Cash Paid	12,000,000
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment	8,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	$ 4,000,000