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Regulatory Matters (Tables) | 3 Months Ended
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Mar. 31, 2013
Regulatory Matters [Abstract] |
Regulatory Assets and Liabilities [Table Text Block] |
Regulatory Assets and Liabilities | March 31, 2013 |  |  | December 31, 2012 |
Millions |  |  |
Current Regulatory Assets (a) |  |  |
Deferred Fuel |  | $18.5 |  |  |  | $22.5 |
Total Current Regulatory Assets | 18.5 |  |  | 22.5 |
Non-Current Regulatory Assets |  |  |
Future Benefit Obligations Under |  |  |
Defined Benefit Pension and Other Postretirement Benefit Plans | 256.1 |  |  | 260.7 |
Income Taxes | 34.5 |  |  | 36.0 |
Asset Retirement Obligation | 12.8 |  |  | 12.1 |
Cost Recovery Riders (b) | 24.1 |  |  | 18.5 |
PPACA Income Tax Deferral | 5.0 |  |  | 5.0 |
Conservation Improvement Program | 0.4 |  |  | 4.3 |
Other | 3.7 |  |  | 3.7 |
Total Non-Current Regulatory Assets | 336.6 |  |  | 340.3 |
Total Regulatory Assets |  | $355.1 |  |  |  | $362.8 |
Non-Current Regulatory Liabilities |  |  |
Income Taxes |  | $18.3 |  |  |  | $19.5 |
Plant Removal Obligations | 18.6 |  |  | 18.1 |
Wholesale and Retail Contra AFUDC | 16.0 |  |  | 15.5 |
Other | 6.3 |  |  | 7.0 |
Total Non-Current Regulatory Liabilities |  | $59.2 |  |  |  | $60.1 |
(a) | Current regulatory assets are included in prepayments and other on the Consolidated Balance Sheet.
(b) | The cost recovery rider regulatory asset is primarily due to capital expenditures related to our Bison Wind Energy Center.

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- Definition The entire disclosure for detailed information about regulatory assets and liabilities, including current and noncurrent assets created when regulatory agencies permit the deferral of costs to the balance sheet that would otherwise be required to appear on the company's income statement and would be charged against current expenses or revenues, as well as current and noncurrent liabilities created when regulatory agencies permit. + References No definition available. + Details
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