Quarterly report pursuant to Section 13 or 15(d)

Leases - Significant Leases (Details)

v3.4.0.3
Leases - Significant Leases (Details)
 3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Dec. 31, 2015
Pinedale Liquids Gathering System [Member]      
Operating Leased Assets [Line Items]      
Percentage of total leased properties 39.90%   40.00%
Percentage of leased property revenue 30.40% 70.40%  
Grand Isle Gathering System [Member]      
Operating Leased Assets [Line Items]      
Percentage of total leased properties 50.10%   50.10%
Percentage of leased property revenue 59.80% 0.00%  
Portland Terminal Facility [Member]      
Operating Leased Assets [Line Items]      
Percentage of total leased properties 9.70%   9.60%
Percentage of leased property revenue 9.70% 20.70%  
Public Service Company of New Mexico [Member]      
Operating Leased Assets [Line Items]      
Percentage of total leased properties 0.00%   0.00%
Percentage of leased property revenue 0.00% 8.70%