Annual report pursuant to Section 13 and 15(d)

NATURE OF OPERATIONS AND ACCOUNTING POLICIES Property and Equipment (Details)

v2.4.1.9
NATURE OF OPERATIONS AND ACCOUNTING POLICIES Property and Equipment (Details) (USD $)
In Millions, unless otherwise specified
 12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Property, Plant and Equipment [Line Items]      
Interest costs capitalized $ 4.7us-gaap_InterestCostsCapitalized $ 1.1us-gaap_InterestCostsCapitalized $ 1.5us-gaap_InterestCostsCapitalized
Helicopter [Member]      
Property, Plant and Equipment [Line Items]      
Useful life 15 years    
Salvage value percentage 40.00%us-gaap_PropertyPlantAndEquipmentSalvageValuePercentage
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_AirTransportationEquipmentMember 		   
Machinery and Equipment [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Useful life 5 years    
Machinery and Equipment [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Useful life 7 years    
Buildings and Leasehold Improvements [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Useful life 10 years    
Buildings and Leasehold Improvements [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Useful life 30 years    
Furniture, Fixtures, Vehicles and Other [Member] | Minimum [Member]      
Property, Plant and Equipment [Line Items]      
Useful life 3 years    
Furniture, Fixtures, Vehicles and Other [Member] | Maximum [Member]      
Property, Plant and Equipment [Line Items]      
Useful life 5 years    
Construction in Progress [Member]      
Property, Plant and Equipment [Line Items]      
Accumulated capitalized interest costs $ 5.0us-gaap_AccumulatedCapitalizedInterestCosts
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_ConstructionInProgressMember 		$ 1.4us-gaap_AccumulatedCapitalizedInterestCosts
/ us-gaap_PropertyPlantAndEquipmentByTypeAxis
= us-gaap_ConstructionInProgressMember