Quarterly report pursuant to Section 13 or 15(d)

Leased Properties and Leases - Significant Leases (Details)

v3.5.0.2
Leased Properties and Leases - Significant Leases (Details)
 3 Months Ended 6 Months Ended
Jun. 30, 2016
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Dec. 31, 2015
Pinedale LGS[Member]          
Operating Leased Assets [Line Items]          
Percentage of total leased properties 39.80%   39.80%   40.00%
Percentage of leased property revenue 30.40% 75.90% 30.40% 73.00%  
Grand Isle Gathering System [Member]          
Operating Leased Assets [Line Items]          
Percentage of total leased properties 50.10%   50.10%   50.10%
Percentage of leased property revenue 59.80% 0.00% 59.80% 0.00%  
Portland Terminal Facility [Member]          
Operating Leased Assets [Line Items]          
Percentage of total leased properties 9.80%   9.80%   9.60%
Percentage of leased property revenue 9.70% 23.80% 9.70% 22.20%  
Public Service Company of New Mexico [Member]          
Operating Leased Assets [Line Items]          
Percentage of total leased properties 0.00%   0.00%   0.00%
Percentage of leased property revenue 0.00% 0.00% 0.00% 4.50%