Segment Information - Schedule of Provisions for Contractual Discounts and Estimated Uncompensated Care as a Percentage of Gross Segment Billings (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting [Abstract]
Provision for contractual discounts	70.00%	60.00%	69.00%	60.00%
Provision for uncompensated care	4.00%	9.00%	4.00%	9.00%