Summary of Significant Accounting Policies - Table 1 (Details)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Concentration of Net Operating Revenues by Payor [Abstract]
Medicare	74.90%	74.10%	74.50%
Managed care and other discount plans, including Medicare Advantage	17.70%	18.60%	18.50%
Medicaid	3.00%	1.80%	1.20%
Other third-party payors	1.70%	1.80%	1.80%
Workers' compensation	0.90%	1.20%	1.20%
Patients	0.60%	1.00%	1.10%
Other income	1.20%	1.50%	1.70%
Total	100.00%	100.00%	100.00%