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Consolidated Balance Sheets (USD $) In Millions, unless otherwise specified | Mar. 31, 2013 | Dec. 31, 2012 | Mar. 31, 2012
--- | --- | --- | ---
Utility Plant: |  |  |
Electric | $ 359.6 | $ 356.9 | $ 339.6
Gas | 429.7 | 424.4 | 390.0
Common | 32.7 | 30.9 | 29.9
Construction Work in Progress | 21.2 | 21.0 | 23.3
Total Utility Plant | 843.2 | 833.2 | 782.8
Less: Accumulated Depreciation | 234.9 | 232.0 | 222.7
Net Utility Plant | 608.3 | 601.2 | 560.1
Current Assets: |  |  |
Cash | 7.5 | 9.8 | 8.2
Accounts Receivable, Net | 60.7 | 45.9 | 47.9
Accrued Revenue | 37.7 | 58.1 | 40.9
Exchange Gas Receivable | 1.7 | 9.4 | 6.2
Gas Inventory | 0.5 | 1.1 | 0.6
Materials and Supplies | 4.6 | 4.1 | 3.9
Prepayments and Other | 5.3 | 4.2 | 5.0
Total Current Assets | 118.0 | 132.6 | 112.7
Noncurrent Assets: |  |  |
Regulatory Assets | 131.4 | 136.0 | 137.9
Other Noncurrent Assets | 18.2 | 16.8 | 20.4
Total Noncurrent Assets | 149.6 | 152.8 | 158.3
TOTAL ASSETS | 875.9 | 886.6 | 831.1
Capitalization: |  |  |
Common Stock Equity | 262.3 | 260.4 | 193.6
Preferred Stock | 0.2 | 0.2 | 2.0
Long-Term Debt, Less Current Portion | 287.2 | 287.3 | 287.7
Total Capitalization | 549.7 | 547.9 | 483.3
Current Liabilities: |  |  |
Long-Term Debt, Current Portion | 0.5 | 0.5 | 0.5
Accounts Payable | 25.8 | 30.9 | 18.7
Short-Term Debt | 32.6 | 49.4 | 77.6
Energy Supply Obligations | 7.1 | 13.8 | 16.1
Current Deferred Income Taxes | 4.9 | 13.4 | 3.9
Dividends Declared and Payable | 4.8 |  | 3.8
Interest Payable | 5.4 | 3.1 | 5.5
Other Current Liabilities | 13.2 | 14.3 | 13.5
Total Current Liabilities | 94.3 | 125.4 | 139.6
Noncurrent Liabilities: |  |  |
Energy Supply Obligations | 3.1 | 3.3 | 4.0
Noncurrent Deferred Income Taxes | 52.5 | 38.7 | 48.2
Cost of Removal Obligations | 53.0 | 51.4 | 47.9
Retirement Benefit Obligations | 107.2 | 103.7 | 89.5
Environmental Obligations | 13.8 | 13.8 | 14.5
Other Noncurrent Liabilities | 2.3 | 2.4 | 4.1
Total Noncurrent Liabilities | 231.9 | 213.3 | 208.2
TOTAL | $ 875.9 | $ 886.6 | $ 831.1

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