Regulatory Assets and Liabilities (Tables)

12 Months Ended

Dec. 31, 2012

RegulatoryAssetsAndLiabilitiesDisclosureAbstract

Regulatory Assets And Liabilities Disclosure [Table Text Block]

Regulatory Assets		2012		2011
Grossed-up deferred taxes on equity funds used
	during construction	$	83.5	$	85.6
Asset retirement obligations			125.1		114.4
Deferred taxes			9.1		10.2
Postretirement benefits other than pension			4.6		5.7
Fuel cost			29.3		26.2
Electric power cost			-		3.3
Other			-		0.4
	Total Regulatory Assets	$	251.6	$	245.8
Regulatory Liabilities		2012		2011
Negative salvage		$	203.8	$	158.1
Deferred cash out			6.2		1.2
Sentinel meter station depreciation			3.9		2.8
Postretirement benefits other than pension			24.7		22.0
Electric power cost			7.7		-
Other			1.2		0.7
	Total Regulatory Liabilities	$	247.5	$	184.8