v3.8.0.1
LONG-TERM DEBT LIABILITIES - Senior Unsecured Debt (Details) - USD ($)
$ in Thousands
Mar. 31, 2018
Dec. 31, 2017
Nov. 17, 2017
Debt Instrument [Line Items]      
Senior Notes $ 415,977 $ 416,584  
Debt Instrument, Interest Rate, Stated Percentage     7.25%
DebtInstrumentFaceAmount     $ 400,000