v3.3.1.900
Summary of Significant Accounting Policies - Provisions for Contractual Discounts and Uncompensated Care Applied to Air Medical Trade Receivables 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]      
Allowance for contractual discounts 65.00% 72.00% 60.00%
Trade Accounts Receivable [Member]      
Provisions For Contractual Discounts And Estimated Uncompensated Care [Line Items]      
Allowance for contractual discounts 56.00% 53.00%  
Allowance for uncompensated care 23.00% 23.00%