Quarterly report pursuant to Section 13 or 15(d)

Leased Properties (Details 1)

v2.4.0.8
Leased Properties (Details 1) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 9 Months Ended
Sep. 30, 2014
mi
kV
Sep. 30, 2013
Sep. 30, 2014
Sep. 30, 2013
Pinedale Liquids Gathering System [Member]
       
Sale Leaseback Transaction [Line Items]        
Length of transmission lines physical assets 150      
Estimated useful lives of assets 26 years      
Eastern Interconnect Project [Member]
       
Sale Leaseback Transaction [Line Items]        
Length of transmission lines physical assets 216      
Power of transmission lines physical assets 345      
Estimated useful lives of assets 20 years      
Amount of depreciation of leased property $ 570 $ 570 $ 1,700 $ 1,100