Annual report pursuant to Section 13 and 15(d)

Leased Properties and Leases (Details)

v3.6.0.2
Leased Properties and Leases (Details)
bbl / d in Thousands, bbl in Millions
 12 Months Ended
Dec. 31, 2017
USD ($)
Jun. 30, 2017
USD ($)
Dec. 31, 2016
USD ($)
a
bbl / d
facility
tank
leased_property
mi
bbl
Jun. 30, 2016
USD ($)
Sale Leaseback Transaction [Line Items]        
Number of significant leased properties | leased_property     3  
Grand Isle Gathering System [Member]        
Sale Leaseback Transaction [Line Items]        
Initial Lease Term     11 years  
Length of offshore pipeline (in miles) | mi     153  
Pipeline capacity (in bbl/day) | bbl / d     120  
Number of acres in the onshore terminal and saltwater disposal system (in acres) | a     16  
Renewal Option     9 years  
Renewal Term, percentage of remaining useful life     75.00%  
Current Monthly Rent Payments       $ 2,625,417
Estimated Useful Life     27 years  
Grand Isle Gathering System [Member] | Forecast [Member]        
Sale Leaseback Transaction [Line Items]        
Current Monthly Rent Payments   $ 2,826,250    
Pinedale Liquids Gathering System [Member]        
Sale Leaseback Transaction [Line Items]        
Initial Lease Term     15 years  
Length of offshore pipeline (in miles) | mi     150  
Number of storage facilities | facility     4  
Renewal Option     5 years  
Current Monthly Rent Payments     $ 1,723,833  
Estimated Useful Life     26 years  
Pinedale Liquids Gathering System [Member] | Forecast [Member]        
Sale Leaseback Transaction [Line Items]        
Current Monthly Rent Payments $ 1,741,933      
Pinedale Liquids Gathering System [Member] | Prudential [Member] | Limited Partner [Member]        
Sale Leaseback Transaction [Line Items]        
Ownership percentage     18.95%  
Pinedale Liquids Gathering System [Member] | Pinedale LP [Member] | General Partner [Member]        
Sale Leaseback Transaction [Line Items]        
Ownership percentage     81.05%  
Portland Terminal Facility [Member]        
Sale Leaseback Transaction [Line Items]        
Initial Lease Term     15 years  
Acres owned (in acres) | a     42  
Number of tanks | tank     84  
Crude oil and petroleum product storage capacity (in bbl) | bbl     1.5  
Renewal Option     5 years  
Current Monthly Rent Payments     $ 513,355  
Estimated Useful Life     30 years  
Minimum [Member]        
Sale Leaseback Transaction [Line Items]        
Initial Lease Term     11 years  
Maximum [Member]        
Sale Leaseback Transaction [Line Items]        
Initial Lease Term     15 years