Voluntary Filing Under Chapter 11 of the United States Bankruptcy Code ("Chapter 11") (Details) - helicopter	Sep. 14, 2016	Jul. 31, 2016
Motions Filed
Property, Plant and Equipment [Line Items]
Number of helicopters		97
Motions Filed | Aircraft Operating Leases
Property, Plant and Equipment [Line Items]
Number of helicopters		84
Motions Filed | Financed Helicopters
Property, Plant and Equipment [Line Items]
Number of helicopters		13
Approved Judicial Ruling
Property, Plant and Equipment [Line Items]
Number of helicopters		65
Approved Judicial Ruling | Subsequent Event [Member]
Property, Plant and Equipment [Line Items]
Number of helicopters	66
Senior Notes | Senior Secured Notes Due 2020
Property, Plant and Equipment [Line Items]
Debt stated interest rate (percent)		9.25%
Senior Notes | Senior Secured Notes Due 2021
Property, Plant and Equipment [Line Items]
Debt stated interest rate (percent)		9.375%