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Consolidated Balance Sheets - USD ($) $ in Millions | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | ---
Current assets: |  |
Cash and cash equivalents | $ 5.8 | $ 56.9
Accounts receivable, less allowance for doubtful accounts | 397.6 | 427.3
Production fuel, at weighted average cost | 98.8 | 83.8
Gas stored underground, at weighted average cost | 43.3 | 67.1
Materials and supplies, at weighted average cost | 81.4 | 72.9
Regulatory assets | 120.2 | 68.1
Deferred tax assets | 0.0 | 150.1
Other | 79.7 | 116.9
Total current assets | 826.8 | 1,043.1
Property, plant and equipment, net | 9,519.1 | 8,938.4
Investments: |  |
Investment in American Transmission Company LLC | 293.3 | 286.5
Other | 53.0 | 58.4
Total investments | 346.3 | 344.9
Other assets: |  |
Regulatory assets | 1,788.4 | 1,715.6
Deferred charges and other | 14.6 | 21.5
Total other assets | 1,803.0 | 1,737.1
Total assets | 12,495.2 | 12,063.5
Current liabilities: |  |
Current maturities of long-term debt | 313.4 | 183.0
Commercial paper | 159.8 | 141.3
Accounts payable | 402.4 | 427.9
Regulatory liabilities | 187.1 | 200.1
Other | 296.6 | 262.4
Total current liabilities | 1,359.3 | 1,214.7
Long-term debt, net (excluding current portion) | 3,522.2 | 3,584.3
Other liabilities: |  |
Deferred tax liabilities | 2,381.2 | 2,321.1
Regulatory liabilities | 550.6 | 621.1
Pension and other benefit obligations | 451.8 | 421.7
Other | 306.0 | 260.1
Total other liabilities | $ 3,689.6 | $ 3,624.0
Commitments and contingencies (Note 16) |  |
Common equity: |  |
Common stock | $ 1.1 | $ 1.1
Additional paid-in capital | 1,663.0 | 1,509.1
Retained earnings | 2,068.9 | 1,938.0
Accumulated other comprehensive loss | (0.4) | (0.6)
Shares in deferred compensation trust - 215,093 and 238,935 shares at a weighted average cost of $39.69 and $37.45 per share | (8.5) | (8.9)
Total common equity | 3,724.1 | 3,438.7
Cumulative preferred stock of Interstate Power and Light Company | 200.0 | 200.0
Noncontrolling interest | 0.0 | 1.8
Total equity | 3,924.1 | 3,640.5
Total liabilities and equity | 12,495.2 | 12,063.5
IPL [Member] |  |
Current assets: |  |
Cash and cash equivalents | 4.5 | 5.3
Accounts receivable, less allowance for doubtful accounts | 200.0 | 216.7
Production fuel, at weighted average cost | 60.2 | 52.7
Gas stored underground, at weighted average cost | 18.2 | 30.8
Materials and supplies, at weighted average cost | 45.7 | 42.0
Regulatory assets | 39.6 | 38.7
Deferred tax assets | 0.0 | 104.0
Other | 28.2 | 65.0
Total current assets | 396.4 | 555.2
Property, plant and equipment, net | 4,925.1 | 4,554.7
Investments: |  |
Total investments | 19.6 | 19.1
Other assets: |  |
Regulatory assets | 1,363.0 | 1,319.2
Deferred charges and other | 5.0 | 2.0
Total other assets | 1,368.0 | 1,321.2
Total assets | 6,709.1 | 6,450.2
Current liabilities: |  |
Current maturities of long-term debt | 0.0 | 150.0
Commercial paper | 0.0 | 0.0
Accounts payable | 197.2 | 259.6
Accounts payable to associated companies | 37.7 | 31.3
Regulatory liabilities | 130.9 | 129.7
Accrued taxes | 67.6 | 45.3
Accrued interest | 28.2 | 25.4
Other | 69.5 | 64.6
Total current liabilities | 531.1 | 705.9
Long-term debt, net (excluding current portion) | 1,856.9 | 1,608.0
Other liabilities: |  |
Deferred tax liabilities | 1,378.0 | 1,370.3
Regulatory liabilities | 358.3 | 453.8
Pension and other benefit obligations | 160.2 | 142.4
Other | 229.3 | 185.5
Total other liabilities | $ 2,125.8 | $ 2,152.0
Commitments and contingencies (Note 16) |  |
Common equity: |  |
Common stock | $ 33.4 | $ 33.4
Additional paid-in capital | 1,407.8 | 1,242.8
Retained earnings | 554.1 | 508.1
Total common equity | 1,995.3 | 1,784.3
Cumulative preferred stock of Interstate Power and Light Company | 200.0 | 200.0
Total equity | 2,195.3 | 1,984.3
Total liabilities and equity | 6,709.1 | 6,450.2
WPL [Member] |  |
Current assets: |  |
Cash and cash equivalents | 0.4 | 46.7
Accounts receivable, less allowance for doubtful accounts | 185.4 | 185.8
Production fuel, at weighted average cost | 38.6 | 31.1
Gas stored underground, at weighted average cost | 25.1 | 36.3
Materials and supplies, at weighted average cost | 33.5 | 29.2
Regulatory assets | 80.6 | 29.4
Prepaid gross receipts tax | 39.2 | 38.0
Deferred tax assets | 0.0 | 37.7
Other | 20.7 | 23.2
Total current assets | 423.5 | 457.4
Property, plant and equipment, net | 4,103.7 | 3,938.9
Investments: |  |
Investment in American Transmission Company LLC | 293.3 | 286.5
Other | 15.4 | 19.5
Total investments | 308.7 | 306.0
Other assets: |  |
Regulatory assets | 425.4 | 396.4
Deferred charges and other | 9.1 | 18.9
Total other assets | 434.5 | 415.3
Total assets | 5,270.4 | 5,117.6
Current liabilities: |  |
Current maturities of long-term debt | 0.0 | 30.6
Commercial paper | 19.9 | 0.0
Accounts payable | 136.0 | 112.9
Accounts payable to associated companies | 21.6 | 25.5
Regulatory liabilities | 56.2 | 70.4
Accrued interest | 23.7 | 24.3
Other | 79.5 | 46.6
Total current liabilities | 336.9 | 310.3
Long-term debt, net (excluding current portion) | 1,533.9 | 1,532.5
Other liabilities: |  |
Deferred tax liabilities | 1,005.4 | 967.1
Regulatory liabilities | 192.3 | 167.3
Capital lease obligations - Sheboygan Falls Energy Facility | 83.6 | 89.4
Pension and other benefit obligations | 188.7 | 180.4
Other | 162.0 | 155.2
Total other liabilities | $ 1,632.0 | $ 1,559.4
Commitments and contingencies (Note 16) |  |
Common equity: |  |
Common stock | $ 66.2 | $ 66.2
Additional paid-in capital | 959.0 | 959.0
Retained earnings | 731.1 | 681.7
Total common equity | 1,756.3 | 1,706.9
Noncontrolling interest | 11.3 | 8.5
Total equity | 1,767.6 | 1,715.4
Total liabilities and equity | $ 5,270.4 | $ 5,117.6

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