Annual report pursuant to Section 13 and 15(d)

Leased Properties and Leases - Additional Information (Details)

v3.8.0.1
Leased Properties and Leases - Additional Information (Details)
customer in Thousands, $ in Thousands
12 Months Ended
Dec. 31, 2015
USD ($)
customer
Apr. 01, 2015
USD ($)
Nov. 01, 2012
USD ($)
Public Service Company of New Mexico [Member]      
Sale Leaseback Transaction [Line Items]      
Undivided interest     40.00%
Lease agreement   $ 7,700  
Number of customers served | customer 500    
Intangible asset amortized     $ 1,100
Lease Revenue [Member]      
Sale Leaseback Transaction [Line Items]      
Amortization of intangible assets $ 73