ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)

6 Months Ended

Jun. 30, 2013

Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]

Schedule of changes, net of tax, in accumulated other comprehensive loss

The following tables show the changes, net of tax, to our accumulated other comprehensive loss during the three and six months ended         June 30, 2013:

Three Months Ended June 30, 2013 (Millions)	Cash Flow Hedges			Defined Benefit Plans			Accumulated Other Comprehensive Income (Loss)
Beginning balance at March 31, 2013	$	(4.2	)	$	(35.1	)	$	(39.3	)
Other comprehensive income before reclassifications	0.6			—			0.6
Amounts reclassified out of accumulated other comprehensive loss	1.5			0.6			2.1
Net current period other comprehensive income	2.1			0.6			2.7
Ending balance at June 30, 2013	$	(2.1	)	$	(34.5	)	$	(36.6	)

Six Months Ended June 30, 2013 (Millions)	Cash Flow Hedges			Defined Benefit Plans			Accumulated Other Comprehensive Income (Loss)
Beginning balance at December 31, 2012	$	(5.2	)	$	(35.7	)	$	(40.9	)
Other comprehensive income before reclassifications	0.7			—			0.7
Amounts reclassified out of accumulated other comprehensive loss	2.4			1.2			3.6
Net current period other comprehensive income	3.1			1.2			4.3
Ending balance at June 30, 2013	$	(2.1	)	$	(34.5	)	$	(36.6	)

Schedule of reclassifications out of accumulated other comprehensive loss

The following table shows the reclassifications out of accumulated other comprehensive loss during the three and six months ended June 30, 2013:

	Amount Reclassified
	Three Months Ended		Six Months Ended
(Millions)	June 30, 2013		June 30, 2013			Affected Line Item in the Statements of Income
Losses on cash flow hedges
Utility commodity derivative contracts	$	—	$	0.2		Operating and maintenance expense(1)
Non-regulated commodity derivative contracts	2.1		3.2			Nonregulated revenues
Interest rate hedges	0.3		0.5			Interest expense
	2.4		3.9			Total before tax
	0.9		1.5			Tax expense
	1.5		2.4			Net of tax
Defined benefit plans
Amortization of prior service costs	—		(0.1		)	(2)
Amortization of actuarial losses	1.0		2.1			(2)
	1.0		2.0			Total before tax
	0.4		0.8			Tax expense
	0.6		1.2			Net of tax
Total reclassifications	$	2.1	$	3.6

⁽¹⁾  This item relates to changes in the price of natural gas used to support utility operations.

⁽²⁾  These items are included in the computation of net periodic benefit cost. See Note 14, "Employee Benefit Plans," foradditional information.