XML 20 R10.htm IDEA: XBRL DOCUMENT  v2.3.0.11
Fair Value Measurements
6 Months Ended
Jun. 30, 2011
Fair Value Measurements [Abstract]  
Fair Value Disclosures [Text Block]
4.  FAIR VALUE MEASUREMENTS.
     We are entitled to collect in rates the amounts necessary to fund our ARO. We deposit monthly, into an external trust account, the revenues specifically designated for ARO. We established the ARO trust account (ARO Trust) on June 30, 2008. The ARO Trust carries a moderate risk portfolio. We measure the financial instruments held in our ARO Trust at fair value. However, in accordance with the ASC Topic 980, Regulated Operations, both realized and unrealized gains and losses of the ARO Trust are recorded as regulatory assets or liabilities.
     The fair value hierarchy prioritizes the inputs used to measure fair value, giving the highest priority to quoted prices in active markets for identical assets or liabilities (Level 1 measurements) and the lowest priority to unobservable inputs (Level 3 measurements). We classify our ARO Trust within Level 1 of the hierarchy. Our ARO Trust consists of the following financial instruments (in millions):
                 
      June 30,     December 31,
      2011     2010
Money market funds
    $ 5.4       $ 1.6  
U.S. equity funds
    12.4       17.4  
International equity funds
    6.6       6.0  
Municipal bond funds
    15.2       15.4  
 
           
 
               
Total
    $ 39.6       $ 40.4  
 
           
     Reclassifications of fair value between Level 1, Level 2, and Level 3 of the fair value hierarchy, if applicable, are made at the end of each quarter. No such transfers occurred during the period ended June 30, 2011.