v3.4.0.3
Segment Information - Schedule of Financial Information Concerning Reportable Operating Segments (Detail) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Segment Reporting Information [Line Items]    
Total operating revenues $ 164,016 $ 204,197
Total segment direct expenses 152,554 169,207
Total selling, general and administrative expenses 11,673 11,237
Total net segment profit (570) 23,692
Interest expense (7,533) (7,170)
(Loss) earnings before income taxes (7,488) 16,984
Reportable Operating Segments [Member]    
Segment Reporting Information [Line Items]    
Total operating revenues 164,016 204,197
Total segment direct expenses [1] 152,554 169,275
Total selling, general and administrative expenses 4,347 3,902
Total direct and selling, general and administrative expenses 156,901 173,177
Total net segment profit 7,115 31,020
Reportable Operating Segments [Member] | Air Medical [Member]    
Segment Reporting Information [Line Items]    
Total operating revenues 70,060 72,385
Total segment direct expenses [1] 57,044 60,039
Total selling, general and administrative expenses 2,595 2,629
Total net segment profit 10,421 9,717
Reportable Operating Segments [Member] | Oil and Gas [Member]    
Segment Reporting Information [Line Items]    
Total operating revenues 88,437 120,396
Total segment direct expenses [1],[2] 91,916 100,331
Total selling, general and administrative expenses 1,528 1,159
Total net segment profit (5,007) 18,906
Reportable Operating Segments [Member] | Technical Services [Member]    
Segment Reporting Information [Line Items]    
Total operating revenues 5,519 11,416
Total segment direct expenses [1] 3,594 8,905
Total selling, general and administrative expenses 224 114
Total net segment profit 1,701 2,397
Segment Reconciling Items [Member]    
Segment Reporting Information [Line Items]    
Other, net [3] 256 469
Interest expense (7,533) (7,170)
Unallocated Selling, General and Administrative Expenses [Member]    
Segment Reporting Information [Line Items]    
Unallocated selling, general and administrative costs [1] $ (7,326) $ (7,335)
[1] Included in segment direct expenses and unallocated selling, general, and administrative costs are the depreciation and amortization expense amounts below: Depreciation and Amortization Expense Quarter Ended March 31, 2016 2015 Segment Direct Expense: Oil and Gas $ 9,918 $ 11,280 Air Medical 4,256 4,097 Technical Services 128 128 Total $ 14,302 $ 15,505 Unallocated SG&A $ 2,671 $ 2,646
[2] Includes Equity in loss of unconsolidated affiliate.
[3] Consists of gains on disposition of property and equipment and other income.