v3.3.1.900
Business Segments and Geographic Areas - Schedule of Financial Information Concerning Reportable Operating Segments (Detail) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2014
Sep. 30, 2014
Jun. 30, 2014
Mar. 31, 2014
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Segment Reporting Information [Line Items]                      
Total operating revenues $ 186,751 $ 214,733 $ 198,547 $ 204,197 $ 210,760 $ 216,294 $ 212,145 $ 197,071 $ 804,228 $ 836,270 $ 856,500
Total segment direct expenses                 687,050 670,007 713,090
Total segment selling, general and administrative expenses                 46,422 43,171 38,820
Total                 70,111 111,640 119,284
Interest expense                 (29,066) (29,510) (29,756)
Loss on debt extinguishment                   (29,833)  
Earnings before income taxes $ 938 $ 14,290 $ 11,044 $ 16,984 $ 11,651 $ 28,277 $ 21,700 $ (8,513) 43,256 53,115 90,141
Reportable Operating Segments [Member]                      
Segment Reporting Information [Line Items]                      
Total operating revenues                 804,228 836,270 856,500
Total segment direct expenses                 687,356 670,103 713,352
Total segment selling, general and administrative expenses                 17,771 14,573 12,935
Total segment expenses                 705,127 684,676 726,287
Total                 99,101 151,594 130,213
Reportable Operating Segments [Member] | Air Medical [Member]                      
Segment Reporting Information [Line Items]                      
Total operating revenues                 312,775 300,212 277,884
Total segment direct expenses                 246,487 243,573 231,880
Total segment selling, general and administrative expenses [1]                 10,455 9,801 8,875
Total                 55,833 46,838 37,129
Interest expense                     (300)
Reportable Operating Segments [Member] | Oil and Gas [Member]                      
Segment Reporting Information [Line Items]                      
Total operating revenues                 459,611 516,909 489,055
Total segment direct expenses [2]                 411,757 411,679 393,251
Total segment selling, general and administrative expenses                 6,511 4,615 4,059
Total                 41,343 100,615 91,745
Reportable Operating Segments [Member] | Technical Services [Member]                      
Segment Reporting Information [Line Items]                      
Total operating revenues                 31,842 19,149 89,561
Total segment direct expenses                 29,112 14,851 88,221
Total segment selling, general and administrative expenses                 805 157 1
Total                 1,925 4,141 1,339
Segment Reconciling Items [Member]                      
Segment Reporting Information [Line Items]                      
Other, net [3]                 1,872 (10,539) 15,569
Interest expense                 (29,066) (29,510) (29,434)
Corporate [Member]                      
Segment Reporting Information [Line Items]                      
Unallocated selling, general and administrative costs                 $ (28,651) $ (28,597) $ (26,207)
[1] Includes interest expense $0.3 million for the year ended December 31, 2013.
[2] Includes equity in loss of unconsolidated affiliate.
[3] Includes gains on disposition of property and equipment and other income.