v3.3.1.900
Summary of Significant Accounting Policies - Schedule of Provisions for Contractual Discounts and Estimated Uncompensated Care Applied to Air Medical Revenues Expressed as Percentage of Total Segment Billings (Detail) - Air Medical [Member]
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Provisions For Contractual Discounts And Estimated Uncompensated Care [Line Items]      
Provision for contractual discounts 65.00% 72.00% 60.00%
Provision for uncompensated care 8.00% 2.00% 10.00%