Other Comprehensive Income (Schedule of Amounts Reclassified Out of Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense, net									$ 976	$ 931	$ 962
Tax benefit									11	449	104
Net loss attributable to Community Health Systems, Inc. stockholders	$ (328)	$ (325)	$ (110)	$ (25)	$ (2,013)	$ (110)	$ (137)	$ (199)	(788)	(2,459)	$ (1,721)
Reclassification, Total before tax										1
Reclassification, net of tax									(9)	(28)
Change in Fair Value of Interest Rate Swaps [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification, net of tax									(8)	(19)
Change in Fair Value of Interest Rate Swaps [Member] | Reclassification out of Accumulated Other Comprehensive Income [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Interest expense, net									(10)	(30)
Tax benefit									2	11
Net loss attributable to Community Health Systems, Inc. stockholders									(8)	(19)
Accumulated Defined Benefit Plans Adjustment, Net Prior Service Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification, Total before tax									(1)	(2)
Accumulated Defined Benefit Plans Adjustment, Net Transition Attributable to Parent [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification, Total before tax									(2)	(13)
Change in Unrecognized Pension Cost Components [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Reclassification, Total before tax									(3)	(16)
Tax benefit									2	7
Reclassification, net of tax									$ (1)	$ (9)