Quarterly Financial Data (Unaudited) (Schedule of Quarterly Financial Data) (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Quarterly Financial Data [Abstract]
Net operating revenues	$ 4,918		$ 4,780		$ 4,765		$ 4,176		$ 3,192		$ 3,174		$ 3,191		$ 3,262		$ 18,639		$ 12,819		$ 12,833
Income from continuing operations before income taxes	230		134		109		(131)		88		35		74		149		342		346		522
Income from continuing operations	165		94		76		(75)		62		28		53		99		260		242		358
Income (loss) from discontinued operations, net of taxes	(29)				(6)		(22)		(10)		(6)		(6)		(3)		(57)		(25)		(12)
Net income (loss) attributable to Community Health Systems, Inc. stockholders	$ 100		$ 62		$ 42		$ (112)		$ 28		$ 4		$ 30		$ 79		$ 92		$ 141		$ 266
Basic earnings (loss) per share attributable to Community Health Systems, Inc. common stockholders (1):
Continuing operations	$ 1.13	[1]	$ 0.55	[1]	$ 0.43	[1]	$ (0.84)	[1]	$ 0.41	[1]	$ 0.11	[1]	$ 0.39	[1]	$ 0.90	[1]	$ 1.33	[1]	$ 1.80	[1]	$ 3.11	[1]
Discontinued operations	$ (0.26)	[1]			$ (0.06)	[1]	$ (0.21)	[1]	$ (0.10)	[1]	$ (0.07)	[1]	$ (0.07)	[1]	$ (0.03)	[1]	$ (0.51)	[1]	$ (0.27)	[1]	$ (0.13)	[1]
Net income (loss)	$ 0.88	[1]	$ 0.55	[1]	$ 0.37	[1]	$ (1.05)	[1]	$ 0.30	[1]	$ 0.04	[1]	$ 0.32	[1]	$ 0.87	[1]	$ 0.82	[1]	$ 1.52	[1]	$ 2.98	[1]
Diluted earnings (loss) per share attributable to Community Health Systems, Inc. common stockholders (1):
Continuing operations	$ 1.12	[1]	$ 0.54	[1]	$ 0.42	[1]	$ (0.84)	[1]	$ 0.40	[1]	$ 0.11	[1]	$ 0.38	[1]	$ 0.89	[1]	$ 1.32	[1]	$ 1.77	[1]	$ 3.09	[1]
Discontinued operations	$ (0.25)	[1]			$ (0.06)	[1]	$ (0.21)	[1]	$ (0.10)	[1]	$ (0.07)	[1]	$ (0.07)	[1]	$ (0.03)	[1]	$ (0.51)	[1]	$ (0.27)	[1]	$ (0.13)	[1]
Net income (loss)	$ 0.87	[1]	$ 0.54	[1]	$ 0.37	[1]	$ (1.05)	[1]	$ 0.30	[1]	$ 0.04	[1]	$ 0.32	[1]	$ 0.86	[1]	$ 0.82	[1]	$ 1.51	[1]	$ 2.96	[1]
Weighted-average number of shares outstanding:
Basic	113,606,631		113,138,663		112,598,899		106,601,997		93,372,398		93,259,027		92,866,370		91,002,615		111,579,088		92,633,332		89,242,949
Diluted	114,828,587		114,343,778		113,474,169		106,601,997		94,703,458		94,483,596		94,109,368		91,998,993		112,549,320		93,815,013		89,806,937

[1] Total per share amounts may not add due to rounding.