Operations and Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2013

Operations and Significant Accounting Policies [Abstract]

Inventories [Table Text Block]

Inventories	September 30, 2013		December 31, 2012
Millions
Fuel		$18.3		$28.0
Materials and Supplies	46.4		41.8
Total Inventories		$64.7		$69.8

Prepayments and Other Current Assets [Table Text Block]

Prepayments and Other Current Assets	September 30, 2013		December 31, 2012
Millions
Deferred Fuel Adjustment Clause		$22.8		$22.5
Other	6.4		11.1
Total Prepayments and Other Current Assets		$29.2		$33.6

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

Other Current Liabilities	September 30, 2013		December 31, 2012
Millions
Customer Deposits		$27.5		$28.8
Other	31.8		33.8
Total Other Current Liabilities		$59.3		$62.6

Other Non-Current Liabilities	September 30, 2013		December 31, 2012
Millions
Asset Retirement Obligation		$82.6		$77.9
Other	46.5		45.4
Total Other Non-Current Liabilities		$129.1		$123.3

Supplemental Statement of Cash Flows Information [Table Text Block]

Supplemental Statement of Cash Flows Information.

For the Nine Months Ended September 30,	2013		2012
Millions
Cash Paid During the Period for Interest – Net of Amounts Capitalized		$36.0		$32.3
Cash Paid During the Period for Income Taxes		$0.6		$0.2
Noncash Investing and Financing Activities
Decrease in Accounts Payable for Capital Additions to Property, Plant and Equipment	$(10.0)		$(13.1)
Capitalized Asset Retirement Costs		$1.9		$2.4
AFUDC – Equity		$3.4		$3.4