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Condensed Consolidated Balance Sheets - USD ($) $ in Millions | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Current assets: |  |
Cash and cash equivalents | $ 139.2 | $ 56.9
Accounts receivable, less allowance for doubtful accounts | 427.3 | 427.3
Production fuel, at weighted average cost | 87.8 | 83.8
Materials and supplies, at weighted average cost | 83.7 | 72.9
Gas stored underground, at weighted average cost | 40.0 | 67.1
Regulatory assets | 92.3 | 68.1
Other | 217.4 | 267.0
Total current assets | 1,087.7 | 1,043.1
Property, plant and equipment, net | 9,366.5 | 8,938.4
Investments: |  |
Investment in American Transmission Company LLC | 296.7 | 286.5
Other | 56.4 | 58.4
Total investments | 353.1 | 344.9
Other assets: |  |
Regulatory assets | 1,715.6 | 1,715.6
Deferred charges and other | 35.7 | 43.9
Total other assets | 1,751.3 | 1,759.5
Total assets | 12,558.6 | 12,085.9
Current liabilities: |  |
Current maturities of long-term debt | 3.0 | 183.0
Commercial paper | 109.1 | 141.3
Accounts payable | 438.3 | 427.9
Regulatory liabilities | 189.7 | 200.1
Other | 250.7 | 262.4
Total current liabilities | 990.8 | 1,214.7
Long-term debt, net (excluding current portion) | 3,855.8 | 3,606.7
Other liabilities: |  |
Deferred income tax liabilities | 2,462.1 | 2,321.1
Regulatory liabilities | 554.4 | 621.1
Pension and other benefit obligations | 416.4 | 421.7
Other | 333.0 | 260.1
Total other liabilities | $ 3,765.9 | $ 3,624.0
Commitments and contingencies (Note 13) |  |
Common equity: |  |
Common stock | $ 1.1 | $ 1.1
Additional paid-in capital | 1,656.0 | 1,509.1
Retained earnings | 2,097.0 | 1,938.0
Accumulated other comprehensive loss | (0.6) | (0.6)
Shares in deferred compensation trust - 210,647 and 238,935 shares at a weighted average cost of $39.28 and $37.45 per share | (8.3) | (8.9)
Total common equity | 3,745.2 | 3,438.7
Cumulative preferred stock of Interstate Power and Light Company | 200.0 | 200.0
Noncontrolling interest | 0.9 | 1.8
Total equity | 3,946.1 | 3,640.5
Total liabilities and equity | 12,558.6 | 12,085.9
IPL [Member] |  |
Current assets: |  |
Cash and cash equivalents | 99.4 | 5.3
Accounts receivable, less allowance for doubtful accounts | 235.7 | 216.7
Production fuel, at weighted average cost | 51.0 | 52.7
Materials and supplies, at weighted average cost | 46.6 | 42.0
Gas stored underground, at weighted average cost | 20.7 | 30.8
Regulatory assets | 33.4 | 38.7
Other | 115.0 | 169.9
Total current assets | 601.8 | 556.1
Property, plant and equipment, net | 4,804.7 | 4,554.7
Investments: |  |
Total investments | 19.4 | 19.1
Other assets: |  |
Regulatory assets | 1,336.8 | 1,319.2
Deferred charges and other | 16.8 | 12.7
Total other assets | 1,353.6 | 1,331.9
Total assets | 6,779.5 | 6,461.8
Current liabilities: |  |
Current maturities of long-term debt | 0.0 | 150.0
Commercial paper | 0.0 |
Accounts payable | 251.3 | 259.6
Accounts payable to associated companies | 49.2 | 31.3
Regulatory liabilities | 126.3 | 129.7
Other | 125.1 | 135.3
Total current liabilities | 551.9 | 705.9
Long-term debt, net (excluding current portion) | 1,868.5 | 1,618.7
Other liabilities: |  |
Deferred income tax liabilities | 1,419.9 | 1,341.4
Regulatory liabilities | 376.2 | 453.8
Pension and other benefit obligations | 141.0 | 142.4
Other | 231.0 | 185.5
Total other liabilities | $ 2,168.1 | $ 2,123.1
Commitments and contingencies (Note 13) |  |
Common equity: |  |
Common stock | $ 33.4 | $ 33.4
Additional paid-in capital | 1,342.8 | 1,242.8
Retained earnings | 614.8 | 537.9
Total common equity | 1,991.0 | 1,814.1
Cumulative preferred stock of Interstate Power and Light Company | 200.0 | 200.0
Total equity | 2,191.0 | 2,014.1
Total liabilities and equity | 6,779.5 | 6,461.8
WPL [Member] |  |
Current assets: |  |
Cash and cash equivalents | 35.7 | 46.7
Accounts receivable, less allowance for doubtful accounts | 173.6 | 185.8
Production fuel, at weighted average cost | 36.8 | 31.1
Materials and supplies, at weighted average cost | 35.3 | 29.2
Gas stored underground, at weighted average cost | 19.3 | 36.3
Regulatory assets | 58.9 | 29.4
Other | 94.1 | 98.7
Total current assets | 453.7 | 457.2
Property, plant and equipment, net | 4,094.4 | 3,938.9
Investments: |  |
Investment in American Transmission Company LLC | 296.7 | 286.5
Other | 19.1 | 19.5
Total investments | 315.8 | 306.0
Other assets: |  |
Regulatory assets | 378.8 | 396.4
Deferred charges and other | 20.3 | 29.7
Total other assets | 399.1 | 426.1
Total assets | 5,263.0 | 5,128.2
Current liabilities: |  |
Current maturities of long-term debt | 0.0 | 30.6
Commercial paper | 0.0 |
Accounts payable | 122.5 | 112.9
Accounts payable to associated companies | 23.3 | 25.5
Regulatory liabilities | 63.4 | 70.4
Other | 86.5 | 70.9
Total current liabilities | 295.7 | 310.3
Long-term debt, net (excluding current portion) | 1,543.6 | 1,543.3
Other liabilities: |  |
Deferred income tax liabilities | 1,030.1 | 970.0
Regulatory liabilities | 178.2 | 167.3
Capital lease obligations - Sheboygan Falls Energy Facility | 85.1 | 89.4
Pension and other benefit obligations | 178.2 | 180.4
Other | 181.6 | 155.2
Total other liabilities | $ 1,653.2 | $ 1,562.3
Commitments and contingencies (Note 13) |  |
Common equity: |  |
Common stock | $ 66.2 | $ 66.2
Additional paid-in capital | 959.0 | 959.0
Retained earnings | 734.4 | 678.6
Total common equity | 1,759.6 | 1,703.8
Noncontrolling interest | 10.9 | 8.5
Total equity | 1,770.5 | 1,712.3
Total liabilities and equity | $ 5,263.0 | $ 5,128.2

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