Contingencies and Legal Claim Costs - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended	12 Months Ended				3 Months Ended
	Oct. 28, 2011 Cases	Dec. 31, 2012	Dec. 31, 2012	Sep. 30, 2013 Hospital	Dec. 31, 2003	Jul. 31, 2012 FLORIDA Hospital	Dec. 31, 2012 Pending Litigation [Member] Health Care Foundation of Greater Kansas City [Member]
Schedule Of Activities Related To Claims Filed [Line Items]
Number of owned and operated hospitals reviewed				95		8
Number of claims filed	3
Capital commitments in connection with purchase of hospitals					$ 450
Legal claim costs		175
Judgment award by the court							162
Period of agreed capital commitments			5 years
Number of year under court-supervisor accounting for expenditures following the purchase			10 years
Plaintiff attorneys fees award							$ 12