Segment Information - Schedule of Provisions for Contractual Discounts and Estimated Uncompensated Care as a Percentage of Gross Billings (Detail)	3 Months Ended		12 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]
Provision for contractual discounts	69.00%	59.00%
Provision for uncompensated care	3.00%	10.00%
Air Medical [Member]
Segment Reporting Information [Line Items]
Gross Air Medical segment billings	100.00%	100.00%	100.00%