Operations and Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2012

Operations and Significant Accounting Policies [Abstract]

Inventories [Table Text Block]

Inventories	September 30, 2012		December 31, 2011
Millions
Fuel		$31.3		$28.6
Materials and Supplies	45.4		40.5
Total Inventories		$76.7		$69.1

Prepayments and Other Current Assets [Table Text Block]

Prepayments and Other Current Assets	September 30, 2012		December 31, 2011
Millions
Deferred Fuel Adjustment Clause		$18.2		$17.5
Other	5.6		9.6
Total Prepayments and Other Current Assets		$23.8		$27.1

Other Current and Non-Current Liabilities [Table Text Block]

Other Current Liabilities	September 30, 2012		December 31, 2011
Millions
Customer Deposits		$28.8		$16.3
Other	24.3		29.3
Total Other Current Liabilities		$53.1		$45.6

Other Non-Current Liabilities	September 30, 2012		December 31, 2011
Millions
Asset Retirement Obligation		$61.7		$57.0
Other	47.7		48.1
Total Other Non-Current Liabilities		$109.4		$105.1

Supplemental Statement of Cash Flows Information [Table Text Block]

Supplemental Statement of Cash Flows Information.

For the Nine Months Ended September 30,	2012		2011
Millions
Cash Paid During the Period for Interest – Net of Amounts Capitalized		$32.3		$32.4
Cash Paid (Received) During the Period for Income Taxes		$0.2	$(11.1)
Noncash Investing and Financing Activities
Decrease in Accounts Payable for Capital Additions to Property, Plant and Equipment	$(13.1)		$(14.8)
AFUDC – Equity		$3.4		$1.7