XML 54 R43.htm IDEA: XBRL DOCUMENT v3.4.0.3
Borrowings and Other Financing Instruments, Credit Facility (Details) - Credit Facility - USD ($)
3 Months Ended
Mar. 31, 2016
Dec. 31, 2015
Line of Credit Facility [Line Items]    
Credit Facility [1] $ 150,000,000  
Drawn [2] 5,000,000  
Available $ 145,000,000  
Debt Instrument, Maturity Date Oct. 31, 2019  
Direct advances on the credit facility outstanding $ 0 $ 0
[1] This credit facility expires in October 2019.
[2] Includes outstanding commercial paper.