Investments

12 Months Ended

Dec. 31, 2012

Investments, Debt and Equity Securities [Abstract]

INVESTMENTS

4. INVESTMENTS.

Available-for-Sale Investments.

       We are entitled to collect in rates the amounts necessary to fund our asset retirement obligations (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.

       Investments in available-for-sale securities within the ARO Trust at fair value were as follows (in millions):

	December 31, 2012				December 31, 2011
	Amortized		Fair		Amortized		Fair
	Cost Basis		Value		Cost Basis		Value
Money Market Funds	$	1.3	$	1.3	$	1.4	$	1.4
U.S. Equity Funds		5.4		7.4		7.1		9.5
International Equity Funds		3.4		3.8		5.4		5.3
Municipal Bond Funds		4.9		5.3		7.9		8.3
Total	$	15.0	$	17.8	$	21.8	$	24.5