| ASSETS |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Current assets: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Cash and cash equivalents |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total cash and cash equivalents
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Short-term investments |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Accounts receivable, less allowance for expected credit losses |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total accounts receivable, less allowance for expected credit losses
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Income tax refunds receivable |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Production fuel, at weighted average cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total production fuel, at weighted average cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Gas stored underground, at weighted average cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total gas stored underground, at weighted average cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Materials and supplies, at weighted average cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total materials and supplies, at weighted average cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Regulatory assets |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total regulatory assets |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Prepaid gross receipts tax |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Income taxes receivable |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total income taxes receivable |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Other |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total other
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Consolidated Variable Interest Entity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total current assets
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Property, plant and equipment, net |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Consolidated Variable Interest Entity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total property, plant and equipment, net
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Investments: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| ATC Holdings |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Other
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total investments |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Other assets: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Regulatory assets |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total regulatory assets |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Deferred charges and other |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total deferred charges and other |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total other assets
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Assets |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total assets
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| LIABILITIES AND EQUITY |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Current liabilities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Current maturities of long-term debt |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total current maturities of long-term debt
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Commercial paper |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total commercial paper |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Other short-term borrowings |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Accounts payable |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total accounts payable
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Accounts payable to associated companies |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Accounts payable to associated companies |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Accrued taxes |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total accrued taxes |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Accrued interest |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total accrued interest |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Regulatory liabilities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total regulatory liabilities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Other |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total other |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total current liabilities
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Long-term debt, net (excluding current portion) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total long-term debt, net (excluding current portion)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Other liabilities: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Deferred tax liabilities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total deferred tax liabilities
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Regulatory liabilities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total regulatory liabilities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Finance lease obligations - Sheboygan Falls Energy Facility |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total finance lease obligations - Sheboygan Falls Energy Facility |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Pension and other benefit obligations |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total pension and other benefit obligations |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Other |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total other
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Consolidated Variable Interest Entity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total other liabilities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Equity: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Common Stock, Shares, Issued |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total common Stock, Shares, Issued |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Common equity: |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Common stock, par value (in dollars per share) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total common stock, par value (in dollars per share)
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Additional paid-in capital |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total additional paid-in capital
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Retained earnings |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total retained earnings
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Accumulated other comprehensive income (loss) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Shares in deferred compensation trust - 351,469 and 367,338 shares at a weighted average cost of $40.46 and $39.05 per share |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Common equity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total common equity
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Cumulative preferred stock of Interstate Power and Light Company |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total cumulative preferred stock of Interstate Power and Light Company |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Noncontrolling interest |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total noncontrolling interest |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Equity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Total equity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| Liabilities and equity |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| IPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| WPL |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Total liabilities and equity
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|