v3.8.0.1
ORGANIZATION AND OPERATIONS Narrative 2 (Details) - USD ($)
$ in Thousands
 12 Months Ended
May 04, 2017
Apr. 28, 2017
Apr. 18, 2017
Feb. 22, 2017
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Feb. 26, 2014
Debt Instrument [Line Items]                
Proceeds from note offering, net of issuance costs         $ 543,333 $ 0 $ 0  
Financing Receivable, Impaired [Line Items]                
Proceeds from Axeon term loan         $ 110,000 $ 0 $ 0  
Common Limited Partner [Member]                
Class of Stock [Line Items]                
Issuance of units (units)     14,375,000   14,375,000 595,050    
Proceeds from common unit issuance including general partner contribution     $ 657,500     $ 28,300    
Net proceeds from issuance of units         $ 643,878 27,710    
Series B Preferred Limited Partner [Member]                
Class of Stock [Line Items]                
Issuance of units (units)   15,400,000            
Preferred units distribution percentage   7.625%            
Net proceeds from issuance of units   $ 371,800            
5.625% senior notes                
Debt Instrument [Line Items]                
Senior notes issued   $ 550,000            
Stated interest rate   5.625%     5.625%      
Proceeds from note offering, net of issuance costs   $ 543,300            
Axeon [Member]                
Financing Receivable, Impaired [Line Items]                
Axeon Term Loan Receivable               $ 190,000
Maximum Amount Guarantees           $ 125,000    
Proceeds from Axeon term loan       $ 110,000        
Navigator Acquisition [Member]                
Business Acquisition [Line Items]                
Purchase price of Navigator Acquisition $ 1,500,000