Quarterly report pursuant to Section 13 or 15(d)

ACQUISITIONS AND DISPOSITIONS (Details)

v3.7.0.1
ACQUISITIONS AND DISPOSITIONS (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2017
USD ($)
acquisition
Mar. 31, 2016
USD ($)
acquisition
Dec. 31, 2016
USD ($)
Property, Plant and Equipment [Line Items]      
Purchases of property and equipment $ 1,005 $ 2,145  
Capitalized interest payments $ 400 $ 0  
Number of helicopter acquisitions | acquisition 0 0  
Proceeds from disposition of property and equipment $ 126 $ 3,980  
Gains on asset dispositions, net 109 $ 2,913  
Construction in Progress      
Property, Plant and Equipment [Line Items]      
Interest capitalized in property and equipment $ 4,900   $ 4,500