Aircraft, Net and Property, Plant and Equipment, Net - Additional Information (Details) |
3 Months Ended | 12 Months Ended | ||||
|---|---|---|---|---|---|---|
|
Sep. 30, 2015
USD ($)
|
Mar. 31, 2015
USD ($)
aircraft
|
Jun. 30, 2014
USD ($)
|
Dec. 31, 2015
USD ($)
|
Dec. 31, 2014
USD ($)
|
Dec. 31, 2013
USD ($)
|
|
| Property, Plant and Equipment [Line Items] | ||||||
| Proceeds from sale-leaseback transactions | $ 24,700,000 | $ 5,078,000 | $ 24,660,000 | $ 0 | ||
| Deferred gain on sale-leaseback transaction | $ 12,300,000 | |||||
| Number of helicopters given in exchange | aircraft | 4 | |||||
| Number of helicopters received in exchange | aircraft | 2 | |||||
| Gain on exchange transaction | $ 0 | |||||
| Depreciation expense | 18,600,000 | 17,800,000 | 13,400,000 | |||
| Medford Hangar | ||||||
| Property, Plant and Equipment [Line Items] | ||||||
| Proceeds from sale-leaseback transactions | $ 5,100,000 | |||||
| Deferred gain on sale-leaseback transaction | $ 900,000 | |||||
| Assets Under Capital Lease and Deferred Overhauls | ||||||
| Property, Plant and Equipment [Line Items] | ||||||
| Amortization expense | $ 20,200,000 | $ 14,700,000 | $ 18,100,000 | |||