Document And Entity Information
Document And Entity Information | 3 Months Ended |
Mar. 31, 2017shares | |
Entity Registrant Name | ALLIANT ENERGY CORP |
Entity Central Index Key | 352,541 |
Current Fiscal Year End Date | --12-31 |
Entity Filer Category | Large Accelerated Filer |
Entity Common Stock, Shares Outstanding | 227,823,278 |
Document Fiscal Year Focus | 2,017 |
Document Fiscal Period Focus | Q1 |
Document Type | 10-Q |
Amendment Flag | false |
Document Period End Date | Mar. 31, 2017 |
IPL [Member] | |
Entity Registrant Name | INTERSTATE POWER & LIGHT CO |
Entity Central Index Key | 52,485 |
Entity Filer Category | Non-accelerated Filer |
Entity Common Stock, Shares Outstanding | 13,370,788 |
WPL [Member] | |
Entity Registrant Name | WISCONSIN POWER & LIGHT CO |
Entity Central Index Key | 107,832 |
Entity Filer Category | Non-accelerated Filer |
Entity Common Stock, Shares Outstanding | 13,236,601 |
Condensed Consolidated Statemen
Condensed Consolidated Statements Of Income - USD ($) shares in Millions, $ in Millions | 3 Months Ended | ||
Mar. 31, 2017 | Mar. 31, 2016 | ||
Operating revenues: | |||
Electric utility | $ 677.6 | $ 668.9 | |
Gas utility | 154.3 | 152.2 | |
Other utility | 11.7 | 13.2 | |
Non-regulated | 10.3 | 9.5 | |
Total operating revenues | 853.9 | 843.8 | |
Operating expenses: | |||
Electric production fuel and purchased power | 207.8 | 200.9 | |
Electric transmission service | 124.7 | 127.9 | |
Cost of gas sold | 92.2 | 95.2 | |
Other operation and maintenance | 152.9 | 145.1 | |
Depreciation and amortization | 107 | 102.5 | |
Taxes other than income taxes | 26.4 | 26.3 | |
Total operating expenses | 711 | 697.9 | |
Operating income | 142.9 | 145.9 | |
Interest expense and other: | |||
Interest expense | 52.3 | 48 | |
Equity income from unconsolidated investments, net | (11.5) | (10.5) | |
Allowance for funds used during construction | (17) | (13.2) | |
Interest income and other | (0.1) | (0.2) | |
Total interest expense and other | 23.7 | 24.1 | |
Income from continuing operations before income taxes | 119.2 | 121.8 | |
Income tax expense (benefit) | 17.6 | 21.6 | |
Income from continuing operations, net of tax | 101.6 | 100.2 | |
Income (loss) from discontinued operations, net of tax | 1.4 | (1.1) | |
Net income | 103 | 99.1 | |
Preferred dividend requirements of Interstate Power and Light Company | 2.6 | 2.6 | |
Net income attributable to common shareowners | $ 100.4 | $ 96.5 | |
Weighted average number of common shares outstanding (basic and diluted) (in shares) | [1] | 227.6 | 226.8 |
Earnings per weighted average common share attributable to Alliant Energy common shareowners (basic and diluted): | |||
Income from continuing operations, net of tax (in dollars per share) | [1] | $ 0.43 | $ 0.43 |
Income from discontinued operations, net of tax (in dollars per share) | [1] | 0.01 | 0 |
Net income (in dollars per share) | [1] | $ 0.44 | $ 0.43 |
Amounts attributable to common shareowners: | |||
Income from continuing operations, net of tax | $ 99 | $ 97.6 | |
Income (loss) from discontinued operations, net of tax | 1.4 | (1.1) | |
Net income attributable to common shareowners | $ 100.4 | $ 96.5 | |
Dividends declared per common share (in dollars per share) | [1] | $ 0.315 | $ 0.29375 |
IPL [Member] | |||
Operating revenues: | |||
Electric utility | $ 356.2 | $ 361.6 | |
Gas utility | 83.1 | 84.2 | |
Other utility | 11.2 | 12.9 | |
Total operating revenues | 450.5 | 458.7 | |
Operating expenses: | |||
Electric production fuel and purchased power | 109.5 | 99.4 | |
Electric transmission service | 81.7 | 86.5 | |
Cost of gas sold | 47.8 | 52.4 | |
Other operation and maintenance | 94.9 | 92 | |
Depreciation and amortization | 53.6 | 52.7 | |
Taxes other than income taxes | 13.4 | 13.7 | |
Total operating expenses | 400.9 | 396.7 | |
Operating income | 49.6 | 62 | |
Interest expense and other: | |||
Interest expense | 27.7 | 24.9 | |
Allowance for funds used during construction | (14.3) | (10.3) | |
Interest income and other | 0.1 | 0 | |
Total interest expense and other | 13.5 | 14.6 | |
Income from continuing operations before income taxes | 36.1 | 47.4 | |
Income tax expense (benefit) | (3.7) | (0.8) | |
Net income | 39.8 | 48.2 | |
Preferred dividend requirements of Interstate Power and Light Company | 2.6 | 2.6 | |
Net income attributable to common shareowners | 37.2 | 45.6 | |
Amounts attributable to common shareowners: | |||
Net income attributable to common shareowners | 37.2 | 45.6 | |
WPL [Member] | |||
Operating revenues: | |||
Electric utility | 321.4 | 307.3 | |
Gas utility | 71.2 | 68 | |
Other utility | 0.5 | 0.3 | |
Total operating revenues | 393.1 | 375.6 | |
Operating expenses: | |||
Electric production fuel and purchased power | 98.3 | 101.5 | |
Electric transmission service | 43 | 41.4 | |
Cost of gas sold | 44.4 | 42.8 | |
Other operation and maintenance | 57 | 52.1 | |
Depreciation and amortization | 52.4 | 47.4 | |
Taxes other than income taxes | 12 | 11.6 | |
Total operating expenses | 307.1 | 296.8 | |
Operating income | 86 | 78.8 | |
Interest expense and other: | |||
Interest expense | 22.9 | 22.9 | |
Equity income from unconsolidated investments, net | 0 | (10.7) | |
Allowance for funds used during construction | (2.7) | (2.9) | |
Interest income and other | (0.1) | (0.1) | |
Total interest expense and other | 20.1 | 9.2 | |
Income from continuing operations before income taxes | 65.9 | 69.6 | |
Income tax expense (benefit) | 20.4 | 22.6 | |
Net income | 45.5 | 47 | |
Net income attributable to noncontrolling interest | 0 | 0.5 | |
Net income attributable to common shareowners | 45.5 | 46.5 | |
Amounts attributable to common shareowners: | |||
Net income attributable to common shareowners | $ 45.5 | $ 46.5 | |
[1] | Amounts reflect the effects of a two-for-one common stock split distributed in May 2016. |
Condensed Consolidated Balance
Condensed Consolidated Balance Sheets - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
Current assets: | ||
Cash and cash equivalents | $ 8.4 | $ 8.2 |
Accounts receivable, less allowance for doubtful accounts | 424.9 | 493.3 |
Production fuel, at weighted average cost | 86.7 | 98.1 |
Gas stored underground, at weighted average cost | 12.2 | 37.6 |
Materials and supplies, at weighted average cost | 88.8 | 86.6 |
Regulatory assets | 58.4 | 57.8 |
Other | 70.4 | 95.5 |
Total current assets | 749.8 | 877.1 |
Property, plant and equipment, net | 10,448.8 | 10,279.2 |
Investments: | ||
Investment in American Transmission Company LLC | 327.7 | 317.6 |
Other | 19.1 | 20 |
Total investments | 346.8 | 337.6 |
Other assets: | ||
Regulatory assets | 1,904.6 | 1,857.3 |
Deferred charges and other | 14.9 | 22.6 |
Total other assets | 1,919.5 | 1,879.9 |
Total assets | 13,464.9 | 13,373.8 |
Current liabilities: | ||
Current maturities of long-term debt | 4.6 | 4.6 |
Commercial paper | 302.8 | 244.1 |
Accounts payable | 369.5 | 445.3 |
Regulatory liabilities | 215.2 | 186.2 |
Other | 272.9 | 281.8 |
Total current liabilities | 1,165 | 1,162 |
Long-term debt, net (excluding current portion) | 4,316.1 | 4,315.6 |
Other liabilities: | ||
Deferred tax liabilities | 2,625.9 | 2,570.2 |
Regulatory liabilities | 481.4 | 494.8 |
Pension and other benefit obligations | 481.7 | 489.9 |
Other | 297.9 | 279.3 |
Total other liabilities | 3,886.9 | 3,834.2 |
Commitments and contingencies (Note 12) | ||
Common equity: | ||
Common stock | 2.3 | 2.3 |
Additional paid-in capital | 1,699.2 | 1,693.1 |
Retained earnings | 2,205.9 | 2,177 |
Accumulated other comprehensive loss | (0.4) | (0.4) |
Shares in deferred compensation trust - 440,704 and 441,695 shares at a weighted average cost of $22.89 and $22.71 per share | (10.1) | (10) |
Total common equity | 3,896.9 | 3,862 |
Cumulative preferred stock of Interstate Power and Light Company | 200 | 200 |
Total equity | 4,096.9 | 4,062 |
Total liabilities and equity | 13,464.9 | 13,373.8 |
IPL [Member] | ||
Current assets: | ||
Cash and cash equivalents | 4.1 | 3.3 |
Accounts receivable, less allowance for doubtful accounts | 177.2 | 240.7 |
Production fuel, at weighted average cost | 64.1 | 70.3 |
Gas stored underground, at weighted average cost | 2.8 | 16.3 |
Materials and supplies, at weighted average cost | 48.8 | 46.5 |
Regulatory assets | 18.4 | 17.7 |
Other | 14.7 | 27.7 |
Total current assets | 330.1 | 422.5 |
Property, plant and equipment, net | 5,503.9 | 5,435.6 |
Other assets: | ||
Regulatory assets | 1,482.4 | 1,441.1 |
Deferred charges and other | 6.6 | 5.5 |
Total other assets | 1,489 | 1,446.6 |
Total assets | 7,323 | 7,304.7 |
Current liabilities: | ||
Commercial paper | 9.2 | 0 |
Accounts payable | 149.2 | 186.3 |
Regulatory liabilities | 166.6 | 149.6 |
Accrued taxes | 37.2 | 53.8 |
Other | 131.5 | 132.1 |
Total current liabilities | 493.7 | 521.8 |
Long-term debt, net (excluding current portion) | 2,154 | 2,153.5 |
Other liabilities: | ||
Deferred tax liabilities | 1,553.2 | 1,511.8 |
Regulatory liabilities | 281.7 | 281.2 |
Pension and other benefit obligations | 172.2 | 173.2 |
Other | 221.1 | 214.2 |
Total other liabilities | 2,228.2 | 2,180.4 |
Commitments and contingencies (Note 12) | ||
Common equity: | ||
Common stock | 33.4 | 33.4 |
Additional paid-in capital | 1,597.8 | 1,597.8 |
Retained earnings | 615.9 | 617.8 |
Total common equity | 2,247.1 | 2,249 |
Cumulative preferred stock of Interstate Power and Light Company | 200 | 200 |
Total equity | 2,447.1 | 2,449 |
Total liabilities and equity | 7,323 | 7,304.7 |
WPL [Member] | ||
Current assets: | ||
Cash and cash equivalents | 2.1 | 4.2 |
Accounts receivable, less allowance for doubtful accounts | 212 | 226.3 |
Production fuel, at weighted average cost | 22.6 | 27.8 |
Gas stored underground, at weighted average cost | 9.4 | 21.3 |
Materials and supplies, at weighted average cost | 36.5 | 36.3 |
Regulatory assets | 40 | 40.1 |
Other | 45.5 | 60.5 |
Total current assets | 368.1 | 416.5 |
Property, plant and equipment, net | 4,523.9 | 4,426.7 |
Other assets: | ||
Regulatory assets | 422.2 | 416.2 |
Deferred charges and other | 20.8 | 30.9 |
Total other assets | 443 | 447.1 |
Total assets | 5,335 | 5,290.3 |
Current liabilities: | ||
Commercial paper | 91.2 | 52.3 |
Accounts payable | 157.2 | 192.9 |
Regulatory liabilities | 48.6 | 36.6 |
Other | 123 | 112.9 |
Total current liabilities | 420 | 394.7 |
Long-term debt, net (excluding current portion) | 1,535.5 | 1,535.2 |
Other liabilities: | ||
Deferred tax liabilities | 984.7 | 971.6 |
Regulatory liabilities | 199.7 | 213.6 |
Capital lease obligations - Sheboygan Falls Energy Facility | 75.5 | 77.2 |
Pension and other benefit obligations | 205.9 | 207.8 |
Other | 168.9 | 159.4 |
Total other liabilities | 1,634.7 | 1,629.6 |
Commitments and contingencies (Note 12) | ||
Common equity: | ||
Common stock | 66.2 | 66.2 |
Additional paid-in capital | 1,019 | 1,019 |
Retained earnings | 659.6 | 645.6 |
Total common equity | 1,744.8 | 1,730.8 |
Total liabilities and equity | $ 5,335 | $ 5,290.3 |
Condensed Consolidated Balance4
Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares | Mar. 31, 2017 | Dec. 31, 2016 |
Common stock, par value | $ 0.01 | $ 0.01 |
Common stock, shares authorized (in shares) | 480,000,000 | 480,000,000 |
Common stock, shares outstanding (in shares) | 227,823,278 | 227,673,654 |
Shares in deferred compensation trust (in shares) | 440,704 | 441,695 |
Shares in deferred compensation trust, weighted average cost per share (in dollars per share) | $ 22.89 | $ 22.71 |
IPL [Member] | ||
Common stock, par value | $ 2.50 | $ 2.50 |
Common stock, shares authorized (in shares) | 24,000,000 | 24,000,000 |
Common stock, shares outstanding (in shares) | 13,370,788 | 13,370,788 |
WPL [Member] | ||
Common stock, par value | $ 5 | $ 5 |
Common stock, shares authorized (in shares) | 18,000,000 | 18,000,000 |
Common stock, shares outstanding (in shares) | 13,236,601 | 13,236,601 |
Condensed Consolidated Stateme5
Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Cash flows from operating activities: | ||
Net income | $ 103 | $ 99.1 |
Adjustments to reconcile net income to net cash flows from operating activities: | ||
Depreciation and amortization | 107 | 102.5 |
Deferred tax expense and tax credits | 22.7 | 22.8 |
Other | (7.6) | (17.6) |
Other changes in assets and liabilities: | ||
Accounts receivable | 36.5 | (47.8) |
Sales of accounts receivable | 35 | 57 |
Gas stored underground | 25.4 | 27.4 |
Regulatory assets | (40.6) | (9.5) |
Derivative assets | 28.1 | 10.7 |
Accounts payable | (41.3) | (31.2) |
Regulatory liabilities | 14.2 | (28.7) |
Deferred income taxes | 32.8 | 20.3 |
Other | 18.5 | 23.3 |
Net cash flows from operating activities | 333.7 | 228.3 |
Cash flows used for investing activities: | ||
Utility business construction and acquisition expenditures | (276.4) | (220.4) |
Alliant Energy Corporate Services, Inc. and non-regulated businesses construction and acquisition expenditures | (15.1) | (18.8) |
Other | (12.1) | 19.2 |
Net cash flows used for investing activities | (303.6) | (220) |
Cash flows from (used for) financing activities: | ||
Common stock dividends | (71.5) | (66.5) |
Net change in commercial paper | 58.7 | 53.6 |
Other | (17.1) | 3.6 |
Net cash flows from (used for) financing activities | (29.9) | (9.3) |
Net increase (decrease) in cash and cash equivalents | 0.2 | (1) |
Cash and cash equivalents at beginning of period | 8.2 | 5.8 |
Cash and cash equivalents at end of period | 8.4 | 4.8 |
Supplemental cash flows information: | ||
Interest, net of capitalized interest | (51.8) | (44.5) |
Income taxes, net | (2.3) | 0 |
Significant non-cash investing and financing activities: | ||
Accrued capital expenditures | 139.3 | 105 |
IPL [Member] | ||
Cash flows from operating activities: | ||
Net income | 39.8 | 48.2 |
Adjustments to reconcile net income to net cash flows from operating activities: | ||
Depreciation and amortization | 53.6 | 52.7 |
Other | 3.1 | 3.2 |
Other changes in assets and liabilities: | ||
Accounts receivable | 32.7 | (37.5) |
Sales of accounts receivable | 35 | 57 |
Regulatory assets | (29.3) | (3.8) |
Accounts payable | (24.7) | (19.5) |
Regulatory liabilities | 15.7 | (23.6) |
Deferred income taxes | 29.1 | 20.9 |
Other | 21.3 | 18.8 |
Net cash flows from operating activities | 176.3 | 116.4 |
Cash flows used for investing activities: | ||
Utility business construction and acquisition expenditures | (127.6) | (135.3) |
Other | (8.7) | 12.1 |
Net cash flows used for investing activities | (136.3) | (123.2) |
Cash flows from (used for) financing activities: | ||
Common stock dividends | (39.1) | (38.1) |
Capital contributions from parent | 0 | 40 |
Other | (0.1) | 3.4 |
Net cash flows from (used for) financing activities | (39.2) | 5.3 |
Net increase (decrease) in cash and cash equivalents | 0.8 | (1.5) |
Cash and cash equivalents at beginning of period | 3.3 | 4.5 |
Cash and cash equivalents at end of period | 4.1 | 3 |
Supplemental cash flows information: | ||
Interest, net of capitalized interest | (28.4) | (22.6) |
Income taxes, net | (2.6) | 1.1 |
Significant non-cash investing and financing activities: | ||
Accrued capital expenditures | 44.2 | 47.6 |
WPL [Member] | ||
Cash flows from operating activities: | ||
Net income | 45.5 | 47 |
Adjustments to reconcile net income to net cash flows from operating activities: | ||
Depreciation and amortization | 52.4 | 47.4 |
Deferred tax expense and tax credits | 11.8 | 18.8 |
Other | 2.6 | (10.9) |
Other changes in assets and liabilities: | ||
Accounts receivable | 13.3 | (8.9) |
Derivative assets | 16.1 | 1 |
Accounts payable | (25.5) | (15.3) |
Derivative liabilities | 8.7 | 19.5 |
Other | 20.7 | 25 |
Net cash flows from operating activities | 145.6 | 123.6 |
Cash flows used for investing activities: | ||
Utility business construction and acquisition expenditures | (141.3) | (85.1) |
Other | (8) | (6.3) |
Net cash flows used for investing activities | (149.3) | (91.4) |
Cash flows from (used for) financing activities: | ||
Common stock dividends | (31.5) | (33.8) |
Net change in commercial paper | 38.9 | 5.6 |
Other | (5.8) | (3.1) |
Net cash flows from (used for) financing activities | 1.6 | (31.3) |
Net increase (decrease) in cash and cash equivalents | (2.1) | 0.9 |
Cash and cash equivalents at beginning of period | 4.2 | 0.4 |
Cash and cash equivalents at end of period | 2.1 | 1.3 |
Supplemental cash flows information: | ||
Interest, net of capitalized interest | (21.9) | (21.9) |
Income taxes, net | 0 | (7.4) |
Significant non-cash investing and financing activities: | ||
Accrued capital expenditures | $ 90.5 | $ 49.7 |
Summary Of Significant Accounti
Summary Of Significant Accounting Policies | 3 Months Ended |
Mar. 31, 2017 | |
Summary Of Significant Accounting Policies | SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K. In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the three months ended March 31, 2017 are not necessarily indicative of results that may be expected for the year ending December 31, 2017 . A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes. Unless otherwise noted, the Notes herein exclude discontinued operations for all periods presented. As required by GAAP, all prior period financial statements and disclosures presented herein, including all Alliant Energy share and per share amounts, have been restated to reflect a two -for-one common stock split distributed in May 2016. NOTE 1(b) New Accounting Standards - Revenue Recognition - In May 2014, the Financial Accounting Standards Board issued an accounting standard providing principles for recognizing revenue for the transfer of promised goods or services to customers with the consideration to which the entity expects to be entitled in exchange for those goods or services. This standard also requires disclosures about the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard can be applied retrospectively to all prior reporting periods presented, or retrospectively with a cumulative effect to the opening retained earnings balance on January 1, 2018 . Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations and do not anticipate a significant change in revenue recognition for retail electric and gas sales, which represent the majority of Alliant Energy’s, IPL’s and WPL’s revenues. Alliant Energy, IPL and WPL continue to evaluate additional impacts of this standard, as well as which transition method will be utilized. Leases - In February 2016, the Financial Accounting Standards Board issued an accounting standard requiring lease assets and lease liabilities, including operating leases, to be recognized on the balance sheet for all leases with terms longer than 12 months. The standard also requires disclosure of key information about leasing arrangements. Alliant Energy, IPL and WPL currently expect to adopt this standard on January 1, 2019 and are evaluating the impact of this standard on their financial condition and results of operations and expect an increase in assets and liabilities from recognizing operating leases on their balance sheets. Presentation of Net Periodic Pension and Postretirement Benefit Costs - In March 2017, the Financial Accounting Standards Board issued an accounting standard amending the income statement presentation of the components of net periodic benefit costs for defined benefit pension and other postretirement plans. The standard requires entities to (1) disaggregate the current service cost component from the other components of net periodic benefit costs and present it with other employee compensation costs in the income statement; and (2) include the other components in the income statement outside of operating income. In addition, only the service cost component of net periodic benefit costs is eligible for capitalization into property, plant and equipment, when applicable. IPL and WPL, as rate-regulated entities, currently expect to capitalize the other components of net periodic benefit costs into regulatory assets or regulatory liabilities, when applicable in accordance with regulations by FERC and various state regulatory commissions. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard must be applied retrospectively for the presentation requirements and prospectively for the capitalization requirements. Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations. |
IPL [Member] | |
Summary Of Significant Accounting Policies | SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K. In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the three months ended March 31, 2017 are not necessarily indicative of results that may be expected for the year ending December 31, 2017 . A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes. Unless otherwise noted, the Notes herein exclude discontinued operations for all periods presented. As required by GAAP, all prior period financial statements and disclosures presented herein, including all Alliant Energy share and per share amounts, have been restated to reflect a two -for-one common stock split distributed in May 2016. NOTE 1(b) New Accounting Standards - Revenue Recognition - In May 2014, the Financial Accounting Standards Board issued an accounting standard providing principles for recognizing revenue for the transfer of promised goods or services to customers with the consideration to which the entity expects to be entitled in exchange for those goods or services. This standard also requires disclosures about the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard can be applied retrospectively to all prior reporting periods presented, or retrospectively with a cumulative effect to the opening retained earnings balance on January 1, 2018 . Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations and do not anticipate a significant change in revenue recognition for retail electric and gas sales, which represent the majority of Alliant Energy’s, IPL’s and WPL’s revenues. Alliant Energy, IPL and WPL continue to evaluate additional impacts of this standard, as well as which transition method will be utilized. Leases - In February 2016, the Financial Accounting Standards Board issued an accounting standard requiring lease assets and lease liabilities, including operating leases, to be recognized on the balance sheet for all leases with terms longer than 12 months. The standard also requires disclosure of key information about leasing arrangements. Alliant Energy, IPL and WPL currently expect to adopt this standard on January 1, 2019 and are evaluating the impact of this standard on their financial condition and results of operations and expect an increase in assets and liabilities from recognizing operating leases on their balance sheets. Presentation of Net Periodic Pension and Postretirement Benefit Costs - In March 2017, the Financial Accounting Standards Board issued an accounting standard amending the income statement presentation of the components of net periodic benefit costs for defined benefit pension and other postretirement plans. The standard requires entities to (1) disaggregate the current service cost component from the other components of net periodic benefit costs and present it with other employee compensation costs in the income statement; and (2) include the other components in the income statement outside of operating income. In addition, only the service cost component of net periodic benefit costs is eligible for capitalization into property, plant and equipment, when applicable. IPL and WPL, as rate-regulated entities, currently expect to capitalize the other components of net periodic benefit costs into regulatory assets or regulatory liabilities, when applicable in accordance with regulations by FERC and various state regulatory commissions. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard must be applied retrospectively for the presentation requirements and prospectively for the capitalization requirements. Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations. |
WPL [Member] | |
Summary Of Significant Accounting Policies | SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES NOTE 1(a) General - The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K. In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the three months ended March 31, 2017 are not necessarily indicative of results that may be expected for the year ending December 31, 2017 . A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes. Unless otherwise noted, the Notes herein exclude discontinued operations for all periods presented. As required by GAAP, all prior period financial statements and disclosures presented herein, including all Alliant Energy share and per share amounts, have been restated to reflect a two -for-one common stock split distributed in May 2016. NOTE 1(b) New Accounting Standards - Revenue Recognition - In May 2014, the Financial Accounting Standards Board issued an accounting standard providing principles for recognizing revenue for the transfer of promised goods or services to customers with the consideration to which the entity expects to be entitled in exchange for those goods or services. This standard also requires disclosures about the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard can be applied retrospectively to all prior reporting periods presented, or retrospectively with a cumulative effect to the opening retained earnings balance on January 1, 2018 . Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations and do not anticipate a significant change in revenue recognition for retail electric and gas sales, which represent the majority of Alliant Energy’s, IPL’s and WPL’s revenues. Alliant Energy, IPL and WPL continue to evaluate additional impacts of this standard, as well as which transition method will be utilized. Leases - In February 2016, the Financial Accounting Standards Board issued an accounting standard requiring lease assets and lease liabilities, including operating leases, to be recognized on the balance sheet for all leases with terms longer than 12 months. The standard also requires disclosure of key information about leasing arrangements. Alliant Energy, IPL and WPL currently expect to adopt this standard on January 1, 2019 and are evaluating the impact of this standard on their financial condition and results of operations and expect an increase in assets and liabilities from recognizing operating leases on their balance sheets. Presentation of Net Periodic Pension and Postretirement Benefit Costs - In March 2017, the Financial Accounting Standards Board issued an accounting standard amending the income statement presentation of the components of net periodic benefit costs for defined benefit pension and other postretirement plans. The standard requires entities to (1) disaggregate the current service cost component from the other components of net periodic benefit costs and present it with other employee compensation costs in the income statement; and (2) include the other components in the income statement outside of operating income. In addition, only the service cost component of net periodic benefit costs is eligible for capitalization into property, plant and equipment, when applicable. IPL and WPL, as rate-regulated entities, currently expect to capitalize the other components of net periodic benefit costs into regulatory assets or regulatory liabilities, when applicable in accordance with regulations by FERC and various state regulatory commissions. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard must be applied retrospectively for the presentation requirements and prospectively for the capitalization requirements. Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations. |
Regulatory Matters
Regulatory Matters | 3 Months Ended |
Mar. 31, 2017 | |
Public Utilities, General Disclosures [Line Items] | |
Regulatory Matters | REGULATORY MATTERS Regulatory Assets and Regulatory Liabilities - Regulatory assets were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Tax-related $1,080.2 $1,055.6 $1,044.9 $1,022.4 $35.3 $33.2 Pension and OPEB costs 568.5 578.7 289.1 294.0 279.4 284.7 Asset retirement obligations 108.6 105.9 67.1 64.3 41.5 41.6 Derivatives 46.4 30.7 17.2 10.0 29.2 20.7 WPL’s EGUs retired early 39.7 41.4 — — 39.7 41.4 Emission allowances 26.0 26.2 26.0 26.2 — — Other 93.6 76.6 56.5 41.9 37.1 34.7 $1,963.0 $1,915.1 $1,500.8 $1,458.8 $462.2 $456.3 Regulatory liabilities were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Cost of removal obligations $413.0 $411.6 $271.1 $269.4 $141.9 $142.2 Electric transmission cost recovery 128.3 72.0 75.9 35.7 52.4 36.3 IPL’s tax benefit riders 64.7 83.5 64.7 83.5 — — Commodity cost recovery 32.9 30.8 20.1 17.8 12.8 13.0 Energy efficiency cost recovery 20.6 20.5 — — 20.6 20.5 Derivatives 9.0 31.5 5.1 12.1 3.9 19.4 Other 28.1 31.1 11.4 12.3 16.7 18.8 $696.6 $681.0 $448.3 $430.8 $248.3 $250.2 Tax-related - Alliant Energy’s and IPL’s tax-related regulatory assets are generally impacted by certain property-related differences at IPL for which deferred tax is not recorded in the income statement pursuant to Iowa rate-making principles. Deferred tax amounts for such property-related differences at IPL are recorded to regulatory assets, along with the necessary revenue requirement tax gross-ups. During the three months ended March 31 , 2017 , Alliant Energy’s and IPL’s tax-related regulatory assets increased primarily due to property-related differences for qualifying repair expenditures. Derivatives - Refer to Note 11 for discussion of derivative assets and derivative liabilities. Electric transmission cost recovery - A group of MISO cooperative and municipal utilities previously filed two complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC and ATC, LLC to determine electric transmission costs billed to utilities, including IPL and WPL. In September 2016, FERC issued an order on the first complaint and established a base return on equity of 10.32% , excluding any incentive adders granted by FERC, effective September 28, 2016, and for the refund period from November 12, 2013 through February 11, 2015 (first complaint period). In the first quarter of 2017, Alliant Energy, IPL and WPL received the refunds for the first complaint period of $51 million , $40 million and $11 million , respectively, subject to final true-up by the end of July 2017. IPL and WPL each recorded the retail portion of the refunds to a regulatory liability. Pursuant to IUB approval, IPL’s retail portion of the refund from ITC will be refunded to its retail customers in 2017 beginning in May 2017. WPL’s retail portion of the refund from ATC, LLC will remain in a regulatory liability until such refunds are approved to be returned to retail customers in a future rate proceeding. IPL’s and WPL’s wholesale customers received their share of the refunds through normal monthly billing practices in the first quarter of 2017. IPL’s tax benefit riders - IPL’s tax benefit riders utilize regulatory liabilities to credit bills of IPL’s Iowa retail electric and gas customers to help offset the impact of rate increases on such customers. These regulatory liabilities are related to tax benefits from tax accounting method changes for repairs expenditures, allocation of mixed service costs, allocation of insurance proceeds from floods in 2008, and cost of removal expenditures. For the three months ended March 31 , 2017 , Alliant Energy’s and IPL’s “IPL’s tax benefit riders” regulatory liabilities decreased by $19 million as follows (in millions): Electric tax benefit rider credits $17 Gas tax benefit rider credits 2 $19 Utility Rate Reviews - IPL’s Retail Electric Rate Review (2016 Test Year) - In April 2017, IPL filed a request with the IUB to increase annual electric rates for its Iowa retail electric customers by $176 million , or approximately 12% . The request was based on a 2016 historical Test Year as adjusted for certain known and measurable changes occurring up to 12 months after the commencement of the proceeding. The key drivers for the filing included recovery of capital projects, primarily power grid modernization and investments that advance cleaner energy, including Marshalltown. An interim retail electric rate increase of $102 million , or approximately 7% , on an annual basis, was implemented effective April 13, 2017, without regulatory review, and will be subject to refund pending determination of final rates. Tax benefit rider credits and MISO transmission owner return on equity refunds are expected to reduce the effect of the rate increase on customer bills in 2017 and 2018. IPL requested a decision from the IUB in 2017 with final rates effective in the first quarter of 2018. The IUB must issue a decision on requests for retail rate changes within 10 months of the date of the application for which changes are filed. WPL’s Retail Electric and Gas Rate Review (2017/2018 Test Period) - In December 2016, WPL received an order from the PSCW authorizing WPL to implement an increase in annual retail electric rates of $9 million , or approximately 1% , and an increase in annual retail gas base rates of $9 million , or approximately 13% . The $9 million net annual retail electric rate increase reflects a $60 million increase in base rates, partially offset by a $51 million reduction in fuel-related costs, using an estimate for 2017 fuel-related costs. These increases were effective January 1, 2017 and extend through the end of 2018. In the first quarter of 2017, Alliant Energy and WPL recorded a $22 million increase in electric revenues and a $2 million increase in gas revenues in conjunction with the base rate increases authorized in the PSCW’s December 2016 order. WPL’s Retail Fuel-related Rate Filing (2017 Test Year) - In March 2017, WPL filed an application with the PSCW for a mid-year fuel-related cost adjustment for 2017. Fuel-related costs for 2017 are currently expected to exceed the approved 2017 fuel-related cost plan by more than the 2% annual bandwidth and result in a deferral of under-collected fuel-related costs of $8 million for 2017. The primary driver for the anticipated under-collection of fuel-related costs is an unplanned extended outage of Riverside during the first half of 2017. WPL’s application proposes to offset any deferral of projected under-collection of fuel-related costs from 2017 against the balance owed to customers for over-collected fuel-related costs for 2016 discussed below, and any remaining net balance at the end of 2017 would then be returned to, or collected from, customers in a future rate proceeding. Under WPL’s proposal, customer rates would not change during 2017 for the mid-year fuel-related cost adjustment. As of March 31, 2017 , fuel-related costs for 2017 outside of the approved bandwidth were $1 million and are included in “Other” in Alliant Energy’s and WPL’s regulatory assets table above. WPL’s Retail Fuel-related Rate Filing (2016 Test Year) - Pursuant to a 2015 PSCW order, WPL’s 2016 fuel-related costs were subject to deferral since they were outside an annual bandwidth of plus or minus 2% of the approved annual forecasted fuel-related costs. Retail fuel-related costs incurred by WPL in 2016 were lower than fuel-related costs used to determine rates for such period resulting in an over-collection of fuel-related costs. As of March 31, 2017 , fuel-related costs for 2016 outside of the approved bandwidth were $9 million and are included in “Commodity cost recovery” in Alliant Energy’s and WPL’s regulatory liabilities table above. |
IPL [Member] | |
Public Utilities, General Disclosures [Line Items] | |
Regulatory Matters | REGULATORY MATTERS Regulatory Assets and Regulatory Liabilities - Regulatory assets were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Tax-related $1,080.2 $1,055.6 $1,044.9 $1,022.4 $35.3 $33.2 Pension and OPEB costs 568.5 578.7 289.1 294.0 279.4 284.7 Asset retirement obligations 108.6 105.9 67.1 64.3 41.5 41.6 Derivatives 46.4 30.7 17.2 10.0 29.2 20.7 WPL’s EGUs retired early 39.7 41.4 — — 39.7 41.4 Emission allowances 26.0 26.2 26.0 26.2 — — Other 93.6 76.6 56.5 41.9 37.1 34.7 $1,963.0 $1,915.1 $1,500.8 $1,458.8 $462.2 $456.3 Regulatory liabilities were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Cost of removal obligations $413.0 $411.6 $271.1 $269.4 $141.9 $142.2 Electric transmission cost recovery 128.3 72.0 75.9 35.7 52.4 36.3 IPL’s tax benefit riders 64.7 83.5 64.7 83.5 — — Commodity cost recovery 32.9 30.8 20.1 17.8 12.8 13.0 Energy efficiency cost recovery 20.6 20.5 — — 20.6 20.5 Derivatives 9.0 31.5 5.1 12.1 3.9 19.4 Other 28.1 31.1 11.4 12.3 16.7 18.8 $696.6 $681.0 $448.3 $430.8 $248.3 $250.2 Tax-related - Alliant Energy’s and IPL’s tax-related regulatory assets are generally impacted by certain property-related differences at IPL for which deferred tax is not recorded in the income statement pursuant to Iowa rate-making principles. Deferred tax amounts for such property-related differences at IPL are recorded to regulatory assets, along with the necessary revenue requirement tax gross-ups. During the three months ended March 31 , 2017 , Alliant Energy’s and IPL’s tax-related regulatory assets increased primarily due to property-related differences for qualifying repair expenditures. Derivatives - Refer to Note 11 for discussion of derivative assets and derivative liabilities. Electric transmission cost recovery - A group of MISO cooperative and municipal utilities previously filed two complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC and ATC, LLC to determine electric transmission costs billed to utilities, including IPL and WPL. In September 2016, FERC issued an order on the first complaint and established a base return on equity of 10.32% , excluding any incentive adders granted by FERC, effective September 28, 2016, and for the refund period from November 12, 2013 through February 11, 2015 (first complaint period). In the first quarter of 2017, Alliant Energy, IPL and WPL received the refunds for the first complaint period of $51 million , $40 million and $11 million , respectively, subject to final true-up by the end of July 2017. IPL and WPL each recorded the retail portion of the refunds to a regulatory liability. Pursuant to IUB approval, IPL’s retail portion of the refund from ITC will be refunded to its retail customers in 2017 beginning in May 2017. WPL’s retail portion of the refund from ATC, LLC will remain in a regulatory liability until such refunds are approved to be returned to retail customers in a future rate proceeding. IPL’s and WPL’s wholesale customers received their share of the refunds through normal monthly billing practices in the first quarter of 2017. IPL’s tax benefit riders - IPL’s tax benefit riders utilize regulatory liabilities to credit bills of IPL’s Iowa retail electric and gas customers to help offset the impact of rate increases on such customers. These regulatory liabilities are related to tax benefits from tax accounting method changes for repairs expenditures, allocation of mixed service costs, allocation of insurance proceeds from floods in 2008, and cost of removal expenditures. For the three months ended March 31 , 2017 , Alliant Energy’s and IPL’s “IPL’s tax benefit riders” regulatory liabilities decreased by $19 million as follows (in millions): Electric tax benefit rider credits $17 Gas tax benefit rider credits 2 $19 Utility Rate Reviews - IPL’s Retail Electric Rate Review (2016 Test Year) - In April 2017, IPL filed a request with the IUB to increase annual electric rates for its Iowa retail electric customers by $176 million , or approximately 12% . The request was based on a 2016 historical Test Year as adjusted for certain known and measurable changes occurring up to 12 months after the commencement of the proceeding. The key drivers for the filing included recovery of capital projects, primarily power grid modernization and investments that advance cleaner energy, including Marshalltown. An interim retail electric rate increase of $102 million , or approximately 7% , on an annual basis, was implemented effective April 13, 2017, without regulatory review, and will be subject to refund pending determination of final rates. Tax benefit rider credits and MISO transmission owner return on equity refunds are expected to reduce the effect of the rate increase on customer bills in 2017 and 2018. IPL requested a decision from the IUB in 2017 with final rates effective in the first quarter of 2018. The IUB must issue a decision on requests for retail rate changes within 10 months of the date of the application for which changes are filed. WPL’s Retail Electric and Gas Rate Review (2017/2018 Test Period) - In December 2016, WPL received an order from the PSCW authorizing WPL to implement an increase in annual retail electric rates of $9 million , or approximately 1% , and an increase in annual retail gas base rates of $9 million , or approximately 13% . The $9 million net annual retail electric rate increase reflects a $60 million increase in base rates, partially offset by a $51 million reduction in fuel-related costs, using an estimate for 2017 fuel-related costs. These increases were effective January 1, 2017 and extend through the end of 2018. In the first quarter of 2017, Alliant Energy and WPL recorded a $22 million increase in electric revenues and a $2 million increase in gas revenues in conjunction with the base rate increases authorized in the PSCW’s December 2016 order. WPL’s Retail Fuel-related Rate Filing (2017 Test Year) - In March 2017, WPL filed an application with the PSCW for a mid-year fuel-related cost adjustment for 2017. Fuel-related costs for 2017 are currently expected to exceed the approved 2017 fuel-related cost plan by more than the 2% annual bandwidth and result in a deferral of under-collected fuel-related costs of $8 million for 2017. The primary driver for the anticipated under-collection of fuel-related costs is an unplanned extended outage of Riverside during the first half of 2017. WPL’s application proposes to offset any deferral of projected under-collection of fuel-related costs from 2017 against the balance owed to customers for over-collected fuel-related costs for 2016 discussed below, and any remaining net balance at the end of 2017 would then be returned to, or collected from, customers in a future rate proceeding. Under WPL’s proposal, customer rates would not change during 2017 for the mid-year fuel-related cost adjustment. As of March 31, 2017 , fuel-related costs for 2017 outside of the approved bandwidth were $1 million and are included in “Other” in Alliant Energy’s and WPL’s regulatory assets table above. WPL’s Retail Fuel-related Rate Filing (2016 Test Year) - Pursuant to a 2015 PSCW order, WPL’s 2016 fuel-related costs were subject to deferral since they were outside an annual bandwidth of plus or minus 2% of the approved annual forecasted fuel-related costs. Retail fuel-related costs incurred by WPL in 2016 were lower than fuel-related costs used to determine rates for such period resulting in an over-collection of fuel-related costs. As of March 31, 2017 , fuel-related costs for 2016 outside of the approved bandwidth were $9 million and are included in “Commodity cost recovery” in Alliant Energy’s and WPL’s regulatory liabilities table above. |
WPL [Member] | |
Public Utilities, General Disclosures [Line Items] | |
Regulatory Matters | REGULATORY MATTERS Regulatory Assets and Regulatory Liabilities - Regulatory assets were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Tax-related $1,080.2 $1,055.6 $1,044.9 $1,022.4 $35.3 $33.2 Pension and OPEB costs 568.5 578.7 289.1 294.0 279.4 284.7 Asset retirement obligations 108.6 105.9 67.1 64.3 41.5 41.6 Derivatives 46.4 30.7 17.2 10.0 29.2 20.7 WPL’s EGUs retired early 39.7 41.4 — — 39.7 41.4 Emission allowances 26.0 26.2 26.0 26.2 — — Other 93.6 76.6 56.5 41.9 37.1 34.7 $1,963.0 $1,915.1 $1,500.8 $1,458.8 $462.2 $456.3 Regulatory liabilities were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Cost of removal obligations $413.0 $411.6 $271.1 $269.4 $141.9 $142.2 Electric transmission cost recovery 128.3 72.0 75.9 35.7 52.4 36.3 IPL’s tax benefit riders 64.7 83.5 64.7 83.5 — — Commodity cost recovery 32.9 30.8 20.1 17.8 12.8 13.0 Energy efficiency cost recovery 20.6 20.5 — — 20.6 20.5 Derivatives 9.0 31.5 5.1 12.1 3.9 19.4 Other 28.1 31.1 11.4 12.3 16.7 18.8 $696.6 $681.0 $448.3 $430.8 $248.3 $250.2 Tax-related - Alliant Energy’s and IPL’s tax-related regulatory assets are generally impacted by certain property-related differences at IPL for which deferred tax is not recorded in the income statement pursuant to Iowa rate-making principles. Deferred tax amounts for such property-related differences at IPL are recorded to regulatory assets, along with the necessary revenue requirement tax gross-ups. During the three months ended March 31 , 2017 , Alliant Energy’s and IPL’s tax-related regulatory assets increased primarily due to property-related differences for qualifying repair expenditures. Derivatives - Refer to Note 11 for discussion of derivative assets and derivative liabilities. Electric transmission cost recovery - A group of MISO cooperative and municipal utilities previously filed two complaints with FERC requesting a reduction to the base return on equity used by MISO transmission owners, including ITC and ATC, LLC to determine electric transmission costs billed to utilities, including IPL and WPL. In September 2016, FERC issued an order on the first complaint and established a base return on equity of 10.32% , excluding any incentive adders granted by FERC, effective September 28, 2016, and for the refund period from November 12, 2013 through February 11, 2015 (first complaint period). In the first quarter of 2017, Alliant Energy, IPL and WPL received the refunds for the first complaint period of $51 million , $40 million and $11 million , respectively, subject to final true-up by the end of July 2017. IPL and WPL each recorded the retail portion of the refunds to a regulatory liability. Pursuant to IUB approval, IPL’s retail portion of the refund from ITC will be refunded to its retail customers in 2017 beginning in May 2017. WPL’s retail portion of the refund from ATC, LLC will remain in a regulatory liability until such refunds are approved to be returned to retail customers in a future rate proceeding. IPL’s and WPL’s wholesale customers received their share of the refunds through normal monthly billing practices in the first quarter of 2017. IPL’s tax benefit riders - IPL’s tax benefit riders utilize regulatory liabilities to credit bills of IPL’s Iowa retail electric and gas customers to help offset the impact of rate increases on such customers. These regulatory liabilities are related to tax benefits from tax accounting method changes for repairs expenditures, allocation of mixed service costs, allocation of insurance proceeds from floods in 2008, and cost of removal expenditures. For the three months ended March 31 , 2017 , Alliant Energy’s and IPL’s “IPL’s tax benefit riders” regulatory liabilities decreased by $19 million as follows (in millions): Electric tax benefit rider credits $17 Gas tax benefit rider credits 2 $19 Utility Rate Reviews - IPL’s Retail Electric Rate Review (2016 Test Year) - In April 2017, IPL filed a request with the IUB to increase annual electric rates for its Iowa retail electric customers by $176 million , or approximately 12% . The request was based on a 2016 historical Test Year as adjusted for certain known and measurable changes occurring up to 12 months after the commencement of the proceeding. The key drivers for the filing included recovery of capital projects, primarily power grid modernization and investments that advance cleaner energy, including Marshalltown. An interim retail electric rate increase of $102 million , or approximately 7% , on an annual basis, was implemented effective April 13, 2017, without regulatory review, and will be subject to refund pending determination of final rates. Tax benefit rider credits and MISO transmission owner return on equity refunds are expected to reduce the effect of the rate increase on customer bills in 2017 and 2018. IPL requested a decision from the IUB in 2017 with final rates effective in the first quarter of 2018. The IUB must issue a decision on requests for retail rate changes within 10 months of the date of the application for which changes are filed. WPL’s Retail Electric and Gas Rate Review (2017/2018 Test Period) - In December 2016, WPL received an order from the PSCW authorizing WPL to implement an increase in annual retail electric rates of $9 million , or approximately 1% , and an increase in annual retail gas base rates of $9 million , or approximately 13% . The $9 million net annual retail electric rate increase reflects a $60 million increase in base rates, partially offset by a $51 million reduction in fuel-related costs, using an estimate for 2017 fuel-related costs. These increases were effective January 1, 2017 and extend through the end of 2018. In the first quarter of 2017, Alliant Energy and WPL recorded a $22 million increase in electric revenues and a $2 million increase in gas revenues in conjunction with the base rate increases authorized in the PSCW’s December 2016 order. WPL’s Retail Fuel-related Rate Filing (2017 Test Year) - In March 2017, WPL filed an application with the PSCW for a mid-year fuel-related cost adjustment for 2017. Fuel-related costs for 2017 are currently expected to exceed the approved 2017 fuel-related cost plan by more than the 2% annual bandwidth and result in a deferral of under-collected fuel-related costs of $8 million for 2017. The primary driver for the anticipated under-collection of fuel-related costs is an unplanned extended outage of Riverside during the first half of 2017. WPL’s application proposes to offset any deferral of projected under-collection of fuel-related costs from 2017 against the balance owed to customers for over-collected fuel-related costs for 2016 discussed below, and any remaining net balance at the end of 2017 would then be returned to, or collected from, customers in a future rate proceeding. Under WPL’s proposal, customer rates would not change during 2017 for the mid-year fuel-related cost adjustment. As of March 31, 2017 , fuel-related costs for 2017 outside of the approved bandwidth were $1 million and are included in “Other” in Alliant Energy’s and WPL’s regulatory assets table above. WPL’s Retail Fuel-related Rate Filing (2016 Test Year) - Pursuant to a 2015 PSCW order, WPL’s 2016 fuel-related costs were subject to deferral since they were outside an annual bandwidth of plus or minus 2% of the approved annual forecasted fuel-related costs. Retail fuel-related costs incurred by WPL in 2016 were lower than fuel-related costs used to determine rates for such period resulting in an over-collection of fuel-related costs. As of March 31, 2017 , fuel-related costs for 2016 outside of the approved bandwidth were $9 million and are included in “Commodity cost recovery” in Alliant Energy’s and WPL’s regulatory liabilities table above. |
Property, Plant and Equipment
Property, Plant and Equipment | 3 Months Ended |
Mar. 31, 2017 | |
Property, Plant and Equipment [Line Items] | |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT Utility - Natural Gas-Fired Generation Projects - IPL’s Marshalltown Generating Station - IPL’s construction of Marshalltown, an approximate 660 MW natural gas-fired combined-cycle EGU, was completed and the EGU was placed into service in April 2017. As of March 31, 2017 , Alliant Energy and IPL recorded capitalized expenditures of $635 million and AFUDC of $79 million for Marshalltown in “Property, plant and equipment, net” on their balance sheets. WPL’s Riverside Expansion - WPL is currently constructing the Riverside expansion, an approximate 730 MW natural gas-fired combined-cycle EGU. Construction began in 2016 and is currently expected to be completed by early 2020. As of March 31, 2017 , Alliant Energy and WPL recorded capitalized expenditures for construction work in progress of $129 million and AFUDC of $3 million for the Riverside expansion in “Property, plant and equipment, net” on their balance sheets. These capital expenditures do not yet reflect any potential impacts from the intent to exercise purchase options by certain WPL electric cooperatives for a partial ownership interest in the Riverside expansion. Wind Generation - Franklin County Wind Farm Transfer - In April 2017, the Franklin County wind farm was transferred from AEF to IPL pursuant to a February 2017 FERC order, at a value of approximately $33 million , subject to final working capital adjustments. The final amount to be recovered for IPL’s electric rate-making purposes will be determined by the IUB as part of IPL’s Iowa retail electric rate review for the 2016 Test Year, which was filed in April 2017. |
IPL [Member] | |
Property, Plant and Equipment [Line Items] | |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT Utility - Natural Gas-Fired Generation Projects - IPL’s Marshalltown Generating Station - IPL’s construction of Marshalltown, an approximate 660 MW natural gas-fired combined-cycle EGU, was completed and the EGU was placed into service in April 2017. As of March 31, 2017 , Alliant Energy and IPL recorded capitalized expenditures of $635 million and AFUDC of $79 million for Marshalltown in “Property, plant and equipment, net” on their balance sheets. WPL’s Riverside Expansion - WPL is currently constructing the Riverside expansion, an approximate 730 MW natural gas-fired combined-cycle EGU. Construction began in 2016 and is currently expected to be completed by early 2020. As of March 31, 2017 , Alliant Energy and WPL recorded capitalized expenditures for construction work in progress of $129 million and AFUDC of $3 million for the Riverside expansion in “Property, plant and equipment, net” on their balance sheets. These capital expenditures do not yet reflect any potential impacts from the intent to exercise purchase options by certain WPL electric cooperatives for a partial ownership interest in the Riverside expansion. Wind Generation - Franklin County Wind Farm Transfer - In April 2017, the Franklin County wind farm was transferred from AEF to IPL pursuant to a February 2017 FERC order, at a value of approximately $33 million , subject to final working capital adjustments. The final amount to be recovered for IPL’s electric rate-making purposes will be determined by the IUB as part of IPL’s Iowa retail electric rate review for the 2016 Test Year, which was filed in April 2017. |
WPL [Member] | |
Property, Plant and Equipment [Line Items] | |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT Utility - Natural Gas-Fired Generation Projects - IPL’s Marshalltown Generating Station - IPL’s construction of Marshalltown, an approximate 660 MW natural gas-fired combined-cycle EGU, was completed and the EGU was placed into service in April 2017. As of March 31, 2017 , Alliant Energy and IPL recorded capitalized expenditures of $635 million and AFUDC of $79 million for Marshalltown in “Property, plant and equipment, net” on their balance sheets. WPL’s Riverside Expansion - WPL is currently constructing the Riverside expansion, an approximate 730 MW natural gas-fired combined-cycle EGU. Construction began in 2016 and is currently expected to be completed by early 2020. As of March 31, 2017 , Alliant Energy and WPL recorded capitalized expenditures for construction work in progress of $129 million and AFUDC of $3 million for the Riverside expansion in “Property, plant and equipment, net” on their balance sheets. These capital expenditures do not yet reflect any potential impacts from the intent to exercise purchase options by certain WPL electric cooperatives for a partial ownership interest in the Riverside expansion. |
Receivables
Receivables | 3 Months Ended |
Mar. 31, 2017 | |
Receivables [Line Items] | |
Receivables | RECEIVABLES Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of March 31, 2017 , IPL sold $221.0 million of receivables to the third party, received $56.0 million in cash proceeds, recorded deferred proceeds of $149.0 million and had $41.8 million of available capacity under its sales of accounts receivable program. For the three months ended March 31 , 2017 and 2016 , IPL’s costs incurred related to the sales of accounts receivable program were not material. IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three months ended March 31 were as follows (in millions): 2017 2016 Maximum outstanding aggregate cash proceeds $79.0 $75.0 Average outstanding aggregate cash proceeds 38.4 39.1 The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions): March 31, 2017 December 31, 2016 Customer accounts receivable $143.7 $157.6 Unbilled utility revenues 76.8 90.4 Other receivables 0.5 0.1 Receivables sold to third party 221.0 248.1 Less: cash proceeds (a) 56.0 21.0 Deferred proceeds 165.0 227.1 Less: allowance for doubtful accounts 16.0 16.0 Fair value of deferred proceeds $149.0 $211.1 (a) Changes in cash proceeds are presented in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s cash flows statements. As of March 31, 2017 , outstanding receivables past due under the Receivables Agreement were $69.9 million . Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three months ended March 31 were as follows (in millions): 2017 2016 Collections reinvested in receivables $501.2 $440.2 Write-offs, net of recoveries 4.6 0.4 In connection with the implementation of IPL’s new customer billing and information system in 2016, IPL postponed the write-off of customer bills for a portion of 2016, resulting in lower write-offs for the three months ended March 31 , 2016. |
IPL [Member] | |
Receivables [Line Items] | |
Receivables | RECEIVABLES Sales of Accounts Receivable - IPL maintains a Receivables Purchase and Sale Agreement (Receivables Agreement) whereby it may sell its customer accounts receivables, unbilled revenues and certain other accounts receivables to a third party through wholly-owned and consolidated special purpose entities. The transfers of receivables meet the criteria for sale accounting established by the transfer of financial assets accounting rules. As of March 31, 2017 , IPL sold $221.0 million of receivables to the third party, received $56.0 million in cash proceeds, recorded deferred proceeds of $149.0 million and had $41.8 million of available capacity under its sales of accounts receivable program. For the three months ended March 31 , 2017 and 2016 , IPL’s costs incurred related to the sales of accounts receivable program were not material. IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three months ended March 31 were as follows (in millions): 2017 2016 Maximum outstanding aggregate cash proceeds $79.0 $75.0 Average outstanding aggregate cash proceeds 38.4 39.1 The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions): March 31, 2017 December 31, 2016 Customer accounts receivable $143.7 $157.6 Unbilled utility revenues 76.8 90.4 Other receivables 0.5 0.1 Receivables sold to third party 221.0 248.1 Less: cash proceeds (a) 56.0 21.0 Deferred proceeds 165.0 227.1 Less: allowance for doubtful accounts 16.0 16.0 Fair value of deferred proceeds $149.0 $211.1 (a) Changes in cash proceeds are presented in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s cash flows statements. As of March 31, 2017 , outstanding receivables past due under the Receivables Agreement were $69.9 million . Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three months ended March 31 were as follows (in millions): 2017 2016 Collections reinvested in receivables $501.2 $440.2 Write-offs, net of recoveries 4.6 0.4 In connection with the implementation of IPL’s new customer billing and information system in 2016, IPL postponed the write-off of customer bills for a portion of 2016, resulting in lower write-offs for the three months ended March 31 , 2016. |
Investments
Investments | 3 Months Ended |
Mar. 31, 2017 | |
Schedule of Investments [Line Items] | |
Investments | INVESTMENTS NOTE 5(a) Unconsolidated Equity Investments - Equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions): Alliant Energy WPL 2017 2016 2017 2016 ATC Investment ($11.5 ) ($10.7 ) $— ($10.7 ) Other — 0.2 — — ($11.5 ) ($10.5 ) $— ($10.7 ) On December 31, 2016, pursuant to a June 2016 PSCW order, WPL Transco, LLC was liquidated and WPL transferred its investment in ATC, LLC to ATI. As a result, WPL no longer records equity income from its prior investment in ATC, LLC. There were no impacts of this transfer to Alliant Energy’s consolidated financial statements. As of December 31, 2016, ATI owns Alliant Energy’s entire investment in ATC. NOTE 5(b) Cash Surrender Value of Life Insurance Policies - During the three months ended March 31 , 2016, certain of Alliant Energy’s and IPL’s company-owned life insurance policies were liquidated. The related proceeds of $26 million and $18 million were recorded in investing activities in Alliant Energy’s and IPL’s cash flows statements, respectively. |
IPL [Member] | |
Schedule of Investments [Line Items] | |
Investments | INVESTMENTS NOTE 5(a) Unconsolidated Equity Investments - Equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions): Alliant Energy WPL 2017 2016 2017 2016 ATC Investment ($11.5 ) ($10.7 ) $— ($10.7 ) Other — 0.2 — — ($11.5 ) ($10.5 ) $— ($10.7 ) On December 31, 2016, pursuant to a June 2016 PSCW order, WPL Transco, LLC was liquidated and WPL transferred its investment in ATC, LLC to ATI. As a result, WPL no longer records equity income from its prior investment in ATC, LLC. There were no impacts of this transfer to Alliant Energy’s consolidated financial statements. As of December 31, 2016, ATI owns Alliant Energy’s entire investment in ATC. NOTE 5(b) Cash Surrender Value of Life Insurance Policies - During the three months ended March 31 , 2016, certain of Alliant Energy’s and IPL’s company-owned life insurance policies were liquidated. The related proceeds of $26 million and $18 million were recorded in investing activities in Alliant Energy’s and IPL’s cash flows statements, respectively. |
WPL [Member] | |
Schedule of Investments [Line Items] | |
Investments | INVESTMENTS NOTE 5(a) Unconsolidated Equity Investments - Equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions): Alliant Energy WPL 2017 2016 2017 2016 ATC Investment ($11.5 ) ($10.7 ) $— ($10.7 ) Other — 0.2 — — ($11.5 ) ($10.5 ) $— ($10.7 ) On December 31, 2016, pursuant to a June 2016 PSCW order, WPL Transco, LLC was liquidated and WPL transferred its investment in ATC, LLC to ATI. As a result, WPL no longer records equity income from its prior investment in ATC, LLC. There were no impacts of this transfer to Alliant Energy’s consolidated financial statements. As of December 31, 2016, ATI owns Alliant Energy’s entire investment in ATC. |
Common Equity
Common Equity | 3 Months Ended |
Mar. 31, 2017 | |
Common Equity [Line Items] | |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows: Shares outstanding, January 1, 2017 227,673,654 Shareowner Direct Plan issuances 190,286 Equity-based compensation plans ( Note 9(b) ) 5,185 Other (45,847 ) Shares outstanding, March 31, 2017 227,823,278 Dividend Restrictions - As of March 31, 2017 , IPL’s amount of retained earnings that were free of dividend restrictions was $616 million . As of March 31, 2017 , WPL’s amount of retained earnings that were free of dividend restrictions was $95 million for the remainder of 2017 . Restricted Net Assets of Subsidiaries - As of March 31, 2017 , the amount of IPL’s and WPL’s net assets that were not available to be transferred to their parent company, Alliant Energy, in the form of loans, advances or cash dividends without the consent of IPL’s and WPL’s regulatory authorities was $1.6 billion and $1.7 billion , respectively. Comprehensive Income - For the three months ended March 31, 2017 and 2016 , Alliant Energy had no other comprehensive income; therefore, its comprehensive income was equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was equal to its net income attributable to Alliant Energy common shareowners for such periods. For the three months ended March 31, 2017 and 2016 , IPL and WPL had no other comprehensive income; therefore, their comprehensive income was equal to their net income and their comprehensive income available for common stock was equal to their earnings available for common stock for such periods. |
IPL [Member] | |
Common Equity [Line Items] | |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows: Shares outstanding, January 1, 2017 227,673,654 Shareowner Direct Plan issuances 190,286 Equity-based compensation plans ( Note 9(b) ) 5,185 Other (45,847 ) Shares outstanding, March 31, 2017 227,823,278 Dividend Restrictions - As of March 31, 2017 , IPL’s amount of retained earnings that were free of dividend restrictions was $616 million . As of March 31, 2017 , WPL’s amount of retained earnings that were free of dividend restrictions was $95 million for the remainder of 2017 . Restricted Net Assets of Subsidiaries - As of March 31, 2017 , the amount of IPL’s and WPL’s net assets that were not available to be transferred to their parent company, Alliant Energy, in the form of loans, advances or cash dividends without the consent of IPL’s and WPL’s regulatory authorities was $1.6 billion and $1.7 billion , respectively. Comprehensive Income - For the three months ended March 31, 2017 and 2016 , Alliant Energy had no other comprehensive income; therefore, its comprehensive income was equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was equal to its net income attributable to Alliant Energy common shareowners for such periods. For the three months ended March 31, 2017 and 2016 , IPL and WPL had no other comprehensive income; therefore, their comprehensive income was equal to their net income and their comprehensive income available for common stock was equal to their earnings available for common stock for such periods. |
WPL [Member] | |
Common Equity [Line Items] | |
Common Equity | COMMON EQUITY Common Share Activity - A summary of Alliant Energy’s common stock activity was as follows: Shares outstanding, January 1, 2017 227,673,654 Shareowner Direct Plan issuances 190,286 Equity-based compensation plans ( Note 9(b) ) 5,185 Other (45,847 ) Shares outstanding, March 31, 2017 227,823,278 Dividend Restrictions - As of March 31, 2017 , IPL’s amount of retained earnings that were free of dividend restrictions was $616 million . As of March 31, 2017 , WPL’s amount of retained earnings that were free of dividend restrictions was $95 million for the remainder of 2017 . Restricted Net Assets of Subsidiaries - As of March 31, 2017 , the amount of IPL’s and WPL’s net assets that were not available to be transferred to their parent company, Alliant Energy, in the form of loans, advances or cash dividends without the consent of IPL’s and WPL’s regulatory authorities was $1.6 billion and $1.7 billion , respectively. Comprehensive Income - For the three months ended March 31, 2017 and 2016 , Alliant Energy had no other comprehensive income; therefore, its comprehensive income was equal to its net income and its comprehensive income attributable to Alliant Energy common shareowners was equal to its net income attributable to Alliant Energy common shareowners for such periods. For the three months ended March 31, 2017 and 2016 , IPL and WPL had no other comprehensive income; therefore, their comprehensive income was equal to their net income and their comprehensive income available for common stock was equal to their earnings available for common stock for such periods. |
Debt
Debt | 3 Months Ended |
Mar. 31, 2017 | |
Debt [Line Items] | |
Debt | DEBT Short-term Debt - Information regarding commercial paper classified as short-term debt was as follows (dollars in millions): Alliant Energy Parent March 31, 2017 (Consolidated) Company IPL WPL Commercial paper outstanding $302.8 $202.4 $9.2 $91.2 Commercial paper weighted average interest rates 1.1% 1.2% 1.2% 0.9% Available credit facility capacity $697.2 $97.6 $290.8 $308.8 Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Maximum amount outstanding (based on daily outstanding balances) $325.5 $242.6 $9.2 $— $113.6 $55.7 Average amount outstanding (based on daily outstanding balances) $276.5 $199.0 $0.1 $— $79.1 $25.8 Weighted average interest rates 0.9% 0.6% 1.1% N/A 0.7% 0.4% |
IPL [Member] | |
Debt [Line Items] | |
Debt | DEBT Short-term Debt - Information regarding commercial paper classified as short-term debt was as follows (dollars in millions): Alliant Energy Parent March 31, 2017 (Consolidated) Company IPL WPL Commercial paper outstanding $302.8 $202.4 $9.2 $91.2 Commercial paper weighted average interest rates 1.1% 1.2% 1.2% 0.9% Available credit facility capacity $697.2 $97.6 $290.8 $308.8 Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Maximum amount outstanding (based on daily outstanding balances) $325.5 $242.6 $9.2 $— $113.6 $55.7 Average amount outstanding (based on daily outstanding balances) $276.5 $199.0 $0.1 $— $79.1 $25.8 Weighted average interest rates 0.9% 0.6% 1.1% N/A 0.7% 0.4% |
WPL [Member] | |
Debt [Line Items] | |
Debt | DEBT Short-term Debt - Information regarding commercial paper classified as short-term debt was as follows (dollars in millions): Alliant Energy Parent March 31, 2017 (Consolidated) Company IPL WPL Commercial paper outstanding $302.8 $202.4 $9.2 $91.2 Commercial paper weighted average interest rates 1.1% 1.2% 1.2% 0.9% Available credit facility capacity $697.2 $97.6 $290.8 $308.8 Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Maximum amount outstanding (based on daily outstanding balances) $325.5 $242.6 $9.2 $— $113.6 $55.7 Average amount outstanding (based on daily outstanding balances) $276.5 $199.0 $0.1 $— $79.1 $25.8 Weighted average interest rates 0.9% 0.6% 1.1% N/A 0.7% 0.4% |
Income Taxes
Income Taxes | 3 Months Ended |
Mar. 31, 2017 | |
Income Taxes [Line Items] | |
Income Taxes | INCOME TAXES Income Tax Rates - The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes. Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % IPL’s tax benefit riders (7.8 ) (8.7 ) (19.4 ) (20.7 ) — — Effect of rate-making on property-related differences (7.5 ) (6.8 ) (17.9 ) (15.2 ) (1.7 ) (0.8 ) Production tax credits (5.9 ) (6.3 ) (6.6 ) (6.7 ) (7.0 ) (6.5 ) Other items, net 1.0 4.5 (1.3 ) 5.9 4.7 4.8 Overall income tax rate 14.8 % 17.7 % (10.2 %) (1.7 %) 31.0 % 32.5 % Deferred Tax Assets and Liabilities - For the three months ended March 31 , 2017 , Alliant Energy’s, IPL’s and WPL’s deferred tax liabilities increased $55.7 million , $41.4 million and $13.1 million , respectively. These increases were primarily due to property-related differences recorded during the three months ended March 31 , 2017 . Alliant Energy’s and IPL’s increases were partially offset by the generation of federal net operating losses recorded during the three months ended March 31 , 2017 , which are primarily due to the accelerated tax depreciation associated with Marshalltown. Carryforwards - At March 31, 2017 , carryforwards and expiration dates were estimated as follows (in millions): Range of Expiration Dates Alliant Energy IPL WPL Federal net operating losses 2030-2037 $633 $315 $217 State net operating losses 2018-2037 696 13 2 Federal tax credits 2022-2037 284 104 118 |
IPL [Member] | |
Income Taxes [Line Items] | |
Income Taxes | INCOME TAXES Income Tax Rates - The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes. Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % IPL’s tax benefit riders (7.8 ) (8.7 ) (19.4 ) (20.7 ) — — Effect of rate-making on property-related differences (7.5 ) (6.8 ) (17.9 ) (15.2 ) (1.7 ) (0.8 ) Production tax credits (5.9 ) (6.3 ) (6.6 ) (6.7 ) (7.0 ) (6.5 ) Other items, net 1.0 4.5 (1.3 ) 5.9 4.7 4.8 Overall income tax rate 14.8 % 17.7 % (10.2 %) (1.7 %) 31.0 % 32.5 % Deferred Tax Assets and Liabilities - For the three months ended March 31 , 2017 , Alliant Energy’s, IPL’s and WPL’s deferred tax liabilities increased $55.7 million , $41.4 million and $13.1 million , respectively. These increases were primarily due to property-related differences recorded during the three months ended March 31 , 2017 . Alliant Energy’s and IPL’s increases were partially offset by the generation of federal net operating losses recorded during the three months ended March 31 , 2017 , which are primarily due to the accelerated tax depreciation associated with Marshalltown. Carryforwards - At March 31, 2017 , carryforwards and expiration dates were estimated as follows (in millions): Range of Expiration Dates Alliant Energy IPL WPL Federal net operating losses 2030-2037 $633 $315 $217 State net operating losses 2018-2037 696 13 2 Federal tax credits 2022-2037 284 104 118 |
WPL [Member] | |
Income Taxes [Line Items] | |
Income Taxes | INCOME TAXES Income Tax Rates - The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes. Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % IPL’s tax benefit riders (7.8 ) (8.7 ) (19.4 ) (20.7 ) — — Effect of rate-making on property-related differences (7.5 ) (6.8 ) (17.9 ) (15.2 ) (1.7 ) (0.8 ) Production tax credits (5.9 ) (6.3 ) (6.6 ) (6.7 ) (7.0 ) (6.5 ) Other items, net 1.0 4.5 (1.3 ) 5.9 4.7 4.8 Overall income tax rate 14.8 % 17.7 % (10.2 %) (1.7 %) 31.0 % 32.5 % Deferred Tax Assets and Liabilities - For the three months ended March 31 , 2017 , Alliant Energy’s, IPL’s and WPL’s deferred tax liabilities increased $55.7 million , $41.4 million and $13.1 million , respectively. These increases were primarily due to property-related differences recorded during the three months ended March 31 , 2017 . Alliant Energy’s and IPL’s increases were partially offset by the generation of federal net operating losses recorded during the three months ended March 31 , 2017 , which are primarily due to the accelerated tax depreciation associated with Marshalltown. Carryforwards - At March 31, 2017 , carryforwards and expiration dates were estimated as follows (in millions): Range of Expiration Dates Alliant Energy IPL WPL Federal net operating losses 2030-2037 $633 $315 $217 State net operating losses 2018-2037 696 13 2 Federal tax credits 2022-2037 284 104 118 |
Benefit Plans
Benefit Plans | 3 Months Ended |
Mar. 31, 2017 | |
Benefit Plans | BENEFIT PLANS NOTE 9(a) Pension and Other Postretirement Benefits Plans - Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three months ended March 31 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans amounts represent those respective amounts for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans amounts represent respective amounts for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan. Defined Benefit Pension Plans OPEB Plans Alliant Energy 2017 2016 2017 2016 Service cost $3.1 $3.2 $1.2 $1.3 Interest cost 12.8 13.3 2.2 2.3 Expected return on plan assets (16.4 ) (16.4 ) (1.5 ) (1.5 ) Amortization of prior service credit (0.1 ) (0.1 ) (0.1 ) (1.0 ) Amortization of actuarial loss 9.4 9.3 1.0 1.2 $8.8 $9.3 $2.8 $2.3 Defined Benefit Pension Plans OPEB Plans IPL 2017 2016 2017 2016 Service cost $1.8 $1.9 $0.5 $0.6 Interest cost 5.9 6.1 0.9 1.0 Expected return on plan assets (7.7 ) (7.7 ) (1.1 ) (1.0 ) Amortization of prior service credit — — — (0.7 ) Amortization of actuarial loss 4.0 4.1 0.5 0.6 $4.0 $4.4 $0.8 $0.5 Defined Benefit Pension Plans OPEB Plans WPL 2017 2016 2017 2016 Service cost $1.2 $1.2 $0.5 $0.5 Interest cost 5.5 5.6 0.9 0.9 Expected return on plan assets (7.1 ) (7.1 ) (0.2 ) (0.2 ) Amortization of prior service cost (credit) — 0.1 (0.1 ) (0.2 ) Amortization of actuarial loss 4.6 4.4 0.4 0.5 $4.2 $4.2 $1.5 $1.5 401(k) Savings Plan - A significant number of employees participate in a defined contribution retirement plan (401(k) savings plan). For the three months ended March 31 , costs related to the 401(k) savings plan, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 401(k) costs $6.5 $6.2 $3.4 $3.1 $2.9 $2.8 NOTE 9(b) Equity-based Compensation Plans - All shares, units and awards included below have been adjusted to reflect the common stock split distributed in May 2016. A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three months ended March 31 was as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 Compensation expense $3.2 $5.3 $1.7 $2.8 $1.4 $2.3 Income tax benefits 1.3 2.2 0.7 1.1 0.5 0.9 As of March 31, 2017 , Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $14.0 million , $7.6 million and $5.9 million , which is expected to be recognized over a weighted average period of between one and two years. Performance Shares and Performance Units - A summary of the performance shares and performance units activity, with amounts representing the target number of awards, was as follows: Performance Shares Performance Units 2017 2016 2017 2016 Nonvested awards, January 1 257,599 288,430 93,320 116,412 Granted 63,804 67,552 21,558 23,918 Vested (99,438 ) (98,186 ) (37,395 ) (42,760 ) Forfeited — (1,230 ) (497 ) (764 ) Nonvested awards, March 31 221,965 256,566 76,986 96,806 Vested Awards - During the three months ended March 31 , certain performance shares and performance units vested, resulting in payouts (a combination of cash and common stock for the performance shares and cash only for the performance units) as follows: Performance Shares Performance Units 2017 2016 2017 2016 2014 Grant 2013 Grant 2014 Grant 2013 Grant Performance awards vested 99,438 98,186 37,395 42,760 Percentage of target number of performance awards 147.5 % 165.0 % 147.5 % 165.0 % Aggregate payout value (in millions) $5.6 $5.1 $1.5 $1.7 Payout - cash (in millions) $5.1 $2.9 $1.5 $1.7 Payout - common stock shares issued 5,185 22,408 N/A N/A Fair Value of Awards - Information related to fair values of nonvested performance shares and performance units at March 31, 2017 , by year of grant, was as follows: Performance Shares Performance Units 2017 Grant 2016 Grant 2015 Grant 2017 Grant 2016 Grant 2015 Grant Nonvested awards at target 63,804 67,355 90,806 21,061 22,657 33,268 Alliant Energy common stock closing price on March 31, 2017 $39.61 $39.61 $39.61 $39.61 $39.61 N/A Alliant Energy common stock closing price on grant date N/A N/A N/A N/A N/A $32.55 Estimated payout percentage based on performance criteria 100 % 160 % 130 % 100 % 160 % 130 % Fair values of each nonvested award $39.61 $63.38 $51.49 $39.61 $63.38 $42.32 Performance-Contingent Restricted Stock - Alliant Energy has not granted any performance-contingent restricted stock since 2015. In 2017, 99,438 performance-contingent restricted shares granted in 2014 vested because the specified performance criteria for such shares were met. There were 90,806 shares of nonvested performance-contingent restricted stock outstanding at March 31, 2017 , with a weighted average grant date fair value of $32.55 . Performance Restricted Stock Units - A summary of the performance restricted stock units activity, with amounts representing the target number of units, was as follows: 2017 2016 Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Nonvested units, January 1 67,355 $33.96 — $— Granted 63,804 39.11 67,552 33.93 Forfeited — — (1,230 ) 33.90 Nonvested units, March 31 131,159 36.46 66,322 33.93 Restricted Stock Units - A summary of the restricted stock units activity was as follows: 2017 2016 Nonvested units, January 1 57,736 — Granted 54,688 57,904 Forfeited — (1,054 ) Nonvested units, March 31 112,424 56,850 Performance-Contingent Cash Awards - Alliant Energy has not granted any performance-contingent cash awards since 2015. In 2017, 79,719 performance-contingent cash awards granted in 2014 vested, resulting in cash payouts valued at $3.1 million . There were 79,616 shares of nonvested performance-contingent cash awards outstanding at March 31, 2017. |
IPL [Member] | |
Benefit Plans | BENEFIT PLANS NOTE 9(a) Pension and Other Postretirement Benefits Plans - Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three months ended March 31 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans amounts represent those respective amounts for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans amounts represent respective amounts for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan. Defined Benefit Pension Plans OPEB Plans Alliant Energy 2017 2016 2017 2016 Service cost $3.1 $3.2 $1.2 $1.3 Interest cost 12.8 13.3 2.2 2.3 Expected return on plan assets (16.4 ) (16.4 ) (1.5 ) (1.5 ) Amortization of prior service credit (0.1 ) (0.1 ) (0.1 ) (1.0 ) Amortization of actuarial loss 9.4 9.3 1.0 1.2 $8.8 $9.3 $2.8 $2.3 Defined Benefit Pension Plans OPEB Plans IPL 2017 2016 2017 2016 Service cost $1.8 $1.9 $0.5 $0.6 Interest cost 5.9 6.1 0.9 1.0 Expected return on plan assets (7.7 ) (7.7 ) (1.1 ) (1.0 ) Amortization of prior service credit — — — (0.7 ) Amortization of actuarial loss 4.0 4.1 0.5 0.6 $4.0 $4.4 $0.8 $0.5 Defined Benefit Pension Plans OPEB Plans WPL 2017 2016 2017 2016 Service cost $1.2 $1.2 $0.5 $0.5 Interest cost 5.5 5.6 0.9 0.9 Expected return on plan assets (7.1 ) (7.1 ) (0.2 ) (0.2 ) Amortization of prior service cost (credit) — 0.1 (0.1 ) (0.2 ) Amortization of actuarial loss 4.6 4.4 0.4 0.5 $4.2 $4.2 $1.5 $1.5 401(k) Savings Plan - A significant number of employees participate in a defined contribution retirement plan (401(k) savings plan). For the three months ended March 31 , costs related to the 401(k) savings plan, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 401(k) costs $6.5 $6.2 $3.4 $3.1 $2.9 $2.8 NOTE 9(b) Equity-based Compensation Plans - All shares, units and awards included below have been adjusted to reflect the common stock split distributed in May 2016. A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three months ended March 31 was as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 Compensation expense $3.2 $5.3 $1.7 $2.8 $1.4 $2.3 Income tax benefits 1.3 2.2 0.7 1.1 0.5 0.9 As of March 31, 2017 , Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $14.0 million , $7.6 million and $5.9 million , which is expected to be recognized over a weighted average period of between one and two years. Performance Shares and Performance Units - A summary of the performance shares and performance units activity, with amounts representing the target number of awards, was as follows: Performance Shares Performance Units 2017 2016 2017 2016 Nonvested awards, January 1 257,599 288,430 93,320 116,412 Granted 63,804 67,552 21,558 23,918 Vested (99,438 ) (98,186 ) (37,395 ) (42,760 ) Forfeited — (1,230 ) (497 ) (764 ) Nonvested awards, March 31 221,965 256,566 76,986 96,806 Vested Awards - During the three months ended March 31 , certain performance shares and performance units vested, resulting in payouts (a combination of cash and common stock for the performance shares and cash only for the performance units) as follows: Performance Shares Performance Units 2017 2016 2017 2016 2014 Grant 2013 Grant 2014 Grant 2013 Grant Performance awards vested 99,438 98,186 37,395 42,760 Percentage of target number of performance awards 147.5 % 165.0 % 147.5 % 165.0 % Aggregate payout value (in millions) $5.6 $5.1 $1.5 $1.7 Payout - cash (in millions) $5.1 $2.9 $1.5 $1.7 Payout - common stock shares issued 5,185 22,408 N/A N/A Fair Value of Awards - Information related to fair values of nonvested performance shares and performance units at March 31, 2017 , by year of grant, was as follows: Performance Shares Performance Units 2017 Grant 2016 Grant 2015 Grant 2017 Grant 2016 Grant 2015 Grant Nonvested awards at target 63,804 67,355 90,806 21,061 22,657 33,268 Alliant Energy common stock closing price on March 31, 2017 $39.61 $39.61 $39.61 $39.61 $39.61 N/A Alliant Energy common stock closing price on grant date N/A N/A N/A N/A N/A $32.55 Estimated payout percentage based on performance criteria 100 % 160 % 130 % 100 % 160 % 130 % Fair values of each nonvested award $39.61 $63.38 $51.49 $39.61 $63.38 $42.32 Performance-Contingent Restricted Stock - Alliant Energy has not granted any performance-contingent restricted stock since 2015. In 2017, 99,438 performance-contingent restricted shares granted in 2014 vested because the specified performance criteria for such shares were met. There were 90,806 shares of nonvested performance-contingent restricted stock outstanding at March 31, 2017 , with a weighted average grant date fair value of $32.55 . Performance Restricted Stock Units - A summary of the performance restricted stock units activity, with amounts representing the target number of units, was as follows: 2017 2016 Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Nonvested units, January 1 67,355 $33.96 — $— Granted 63,804 39.11 67,552 33.93 Forfeited — — (1,230 ) 33.90 Nonvested units, March 31 131,159 36.46 66,322 33.93 Restricted Stock Units - A summary of the restricted stock units activity was as follows: 2017 2016 Nonvested units, January 1 57,736 — Granted 54,688 57,904 Forfeited — (1,054 ) Nonvested units, March 31 112,424 56,850 Performance-Contingent Cash Awards - Alliant Energy has not granted any performance-contingent cash awards since 2015. In 2017, 79,719 performance-contingent cash awards granted in 2014 vested, resulting in cash payouts valued at $3.1 million . There were 79,616 shares of nonvested performance-contingent cash awards outstanding at March 31, 2017. |
WPL [Member] | |
Benefit Plans | BENEFIT PLANS NOTE 9(a) Pension and Other Postretirement Benefits Plans - Net Periodic Benefit Costs - The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three months ended March 31 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans amounts represent those respective amounts for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans amounts represent respective amounts for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan. Defined Benefit Pension Plans OPEB Plans Alliant Energy 2017 2016 2017 2016 Service cost $3.1 $3.2 $1.2 $1.3 Interest cost 12.8 13.3 2.2 2.3 Expected return on plan assets (16.4 ) (16.4 ) (1.5 ) (1.5 ) Amortization of prior service credit (0.1 ) (0.1 ) (0.1 ) (1.0 ) Amortization of actuarial loss 9.4 9.3 1.0 1.2 $8.8 $9.3 $2.8 $2.3 Defined Benefit Pension Plans OPEB Plans IPL 2017 2016 2017 2016 Service cost $1.8 $1.9 $0.5 $0.6 Interest cost 5.9 6.1 0.9 1.0 Expected return on plan assets (7.7 ) (7.7 ) (1.1 ) (1.0 ) Amortization of prior service credit — — — (0.7 ) Amortization of actuarial loss 4.0 4.1 0.5 0.6 $4.0 $4.4 $0.8 $0.5 Defined Benefit Pension Plans OPEB Plans WPL 2017 2016 2017 2016 Service cost $1.2 $1.2 $0.5 $0.5 Interest cost 5.5 5.6 0.9 0.9 Expected return on plan assets (7.1 ) (7.1 ) (0.2 ) (0.2 ) Amortization of prior service cost (credit) — 0.1 (0.1 ) (0.2 ) Amortization of actuarial loss 4.6 4.4 0.4 0.5 $4.2 $4.2 $1.5 $1.5 401(k) Savings Plan - A significant number of employees participate in a defined contribution retirement plan (401(k) savings plan). For the three months ended March 31 , costs related to the 401(k) savings plan, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 401(k) costs $6.5 $6.2 $3.4 $3.1 $2.9 $2.8 NOTE 9(b) Equity-based Compensation Plans - All shares, units and awards included below have been adjusted to reflect the common stock split distributed in May 2016. A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three months ended March 31 was as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 Compensation expense $3.2 $5.3 $1.7 $2.8 $1.4 $2.3 Income tax benefits 1.3 2.2 0.7 1.1 0.5 0.9 As of March 31, 2017 , Alliant Energy’s, IPL’s and WPL’s total unrecognized compensation cost related to share-based compensation awards was $14.0 million , $7.6 million and $5.9 million , which is expected to be recognized over a weighted average period of between one and two years. Performance Shares and Performance Units - A summary of the performance shares and performance units activity, with amounts representing the target number of awards, was as follows: Performance Shares Performance Units 2017 2016 2017 2016 Nonvested awards, January 1 257,599 288,430 93,320 116,412 Granted 63,804 67,552 21,558 23,918 Vested (99,438 ) (98,186 ) (37,395 ) (42,760 ) Forfeited — (1,230 ) (497 ) (764 ) Nonvested awards, March 31 221,965 256,566 76,986 96,806 Vested Awards - During the three months ended March 31 , certain performance shares and performance units vested, resulting in payouts (a combination of cash and common stock for the performance shares and cash only for the performance units) as follows: Performance Shares Performance Units 2017 2016 2017 2016 2014 Grant 2013 Grant 2014 Grant 2013 Grant Performance awards vested 99,438 98,186 37,395 42,760 Percentage of target number of performance awards 147.5 % 165.0 % 147.5 % 165.0 % Aggregate payout value (in millions) $5.6 $5.1 $1.5 $1.7 Payout - cash (in millions) $5.1 $2.9 $1.5 $1.7 Payout - common stock shares issued 5,185 22,408 N/A N/A Fair Value of Awards - Information related to fair values of nonvested performance shares and performance units at March 31, 2017 , by year of grant, was as follows: Performance Shares Performance Units 2017 Grant 2016 Grant 2015 Grant 2017 Grant 2016 Grant 2015 Grant Nonvested awards at target 63,804 67,355 90,806 21,061 22,657 33,268 Alliant Energy common stock closing price on March 31, 2017 $39.61 $39.61 $39.61 $39.61 $39.61 N/A Alliant Energy common stock closing price on grant date N/A N/A N/A N/A N/A $32.55 Estimated payout percentage based on performance criteria 100 % 160 % 130 % 100 % 160 % 130 % Fair values of each nonvested award $39.61 $63.38 $51.49 $39.61 $63.38 $42.32 Performance-Contingent Restricted Stock - Alliant Energy has not granted any performance-contingent restricted stock since 2015. In 2017, 99,438 performance-contingent restricted shares granted in 2014 vested because the specified performance criteria for such shares were met. There were 90,806 shares of nonvested performance-contingent restricted stock outstanding at March 31, 2017 , with a weighted average grant date fair value of $32.55 . Performance Restricted Stock Units - A summary of the performance restricted stock units activity, with amounts representing the target number of units, was as follows: 2017 2016 Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Nonvested units, January 1 67,355 $33.96 — $— Granted 63,804 39.11 67,552 33.93 Forfeited — — (1,230 ) 33.90 Nonvested units, March 31 131,159 36.46 66,322 33.93 Restricted Stock Units - A summary of the restricted stock units activity was as follows: 2017 2016 Nonvested units, January 1 57,736 — Granted 54,688 57,904 Forfeited — (1,054 ) Nonvested units, March 31 112,424 56,850 Performance-Contingent Cash Awards - Alliant Energy has not granted any performance-contingent cash awards since 2015. In 2017, 79,719 performance-contingent cash awards granted in 2014 vested, resulting in cash payouts valued at $3.1 million . There were 79,616 shares of nonvested performance-contingent cash awards outstanding at March 31, 2017. |
Fair Value Measurements
Fair Value Measurements | 3 Months Ended |
Mar. 31, 2017 | |
Fair Value Measurements | FAIR VALUE MEASUREMENTS Valuation Hierarchy - At each reporting date, Level 1 items included IPL’s 5.1% cumulative preferred stock, Level 2 items included certain non-exchange traded commodity contracts and substantially all of the long-term debt instruments, and Level 3 items included FTRs, certain non-exchange traded commodity contracts and IPL’s deferred proceeds. Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions): Alliant Energy March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $13.3 $— $1.7 $11.6 $13.3 $41.4 $— $4.6 $36.8 $41.4 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 45.3 — 0.8 44.5 45.3 28.6 — 0.5 28.1 28.6 Long-term debt (including current maturities) 4,320.7 — 4,768.3 2.9 4,771.2 4,320.2 — 4,795.7 3.3 4,799.0 Cumulative preferred stock of IPL 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 IPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $8.8 $— $1.3 $7.5 $8.8 $20.8 $— $2.8 $18.0 $20.8 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 16.3 — 0.5 15.8 16.3 8.3 — 0.4 7.9 8.3 Long-term debt 2,154.0 — 2,342.1 — 2,342.1 2,153.5 — 2,352.3 — 2,352.3 Cumulative preferred stock 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 WPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $4.5 $— $0.4 $4.1 $4.5 $20.6 $— $1.8 $18.8 $20.6 Liabilities: Derivatives 29.0 — 0.3 28.7 29.0 20.3 — 0.1 20.2 20.3 Long-term debt 1,535.5 — 1,790.9 — 1,790.9 1,535.2 — 1,807.4 — 1,807.4 Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions): Alliant Energy Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $8.7 ($32.7 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (35.2 ) (31.4 ) — — Transfers into Level 3 — 0.9 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (6.3 ) (2.1 ) (62.1 ) (17.8 ) Ending balance, March 31 ($32.9 ) ($65.9 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($33.7 ) ($30.0 ) $— $— IPL Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $10.1 ($1.9 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (12.7 ) (7.6 ) — — Transfers into Level 3 — 0.5 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (5.6 ) (3.5 ) (62.1 ) (17.8 ) Ending balance, March 31 ($8.3 ) ($13.1 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($11.4 ) ($6.6 ) $— $— WPL Commodity Contract Derivative Assets and (Liabilities), net Three Months Ended March 31 2017 2016 Beginning balance, January 1 ($1.4 ) ($30.8 ) Total net losses included in changes in net assets (realized/unrealized) (22.5 ) (23.8 ) Transfers into Level 3 — 0.4 Settlements (0.7 ) 1.4 Ending balance, March 31 ($24.6 ) ($52.8 ) The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($22.3 ) ($23.4 ) (a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold. Commodity Contracts - The fair value of electric, natural gas and coal commodity contracts categorized as Level 3 was recognized as net derivative assets (liabilities) as follows (in millions): Alliant Energy IPL WPL Excluding FTRs FTRs Excluding FTRs FTRs Excluding FTRs FTRs March 31, 2017 ($37.0 ) $4.1 ($11.6 ) $3.3 ($25.4 ) $0.8 December 31, 2016 (2.3 ) 11.0 0.1 10.0 (2.4 ) 1.0 |
IPL [Member] | |
Fair Value Measurements | FAIR VALUE MEASUREMENTS Valuation Hierarchy - At each reporting date, Level 1 items included IPL’s 5.1% cumulative preferred stock, Level 2 items included certain non-exchange traded commodity contracts and substantially all of the long-term debt instruments, and Level 3 items included FTRs, certain non-exchange traded commodity contracts and IPL’s deferred proceeds. Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions): Alliant Energy March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $13.3 $— $1.7 $11.6 $13.3 $41.4 $— $4.6 $36.8 $41.4 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 45.3 — 0.8 44.5 45.3 28.6 — 0.5 28.1 28.6 Long-term debt (including current maturities) 4,320.7 — 4,768.3 2.9 4,771.2 4,320.2 — 4,795.7 3.3 4,799.0 Cumulative preferred stock of IPL 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 IPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $8.8 $— $1.3 $7.5 $8.8 $20.8 $— $2.8 $18.0 $20.8 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 16.3 — 0.5 15.8 16.3 8.3 — 0.4 7.9 8.3 Long-term debt 2,154.0 — 2,342.1 — 2,342.1 2,153.5 — 2,352.3 — 2,352.3 Cumulative preferred stock 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 WPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $4.5 $— $0.4 $4.1 $4.5 $20.6 $— $1.8 $18.8 $20.6 Liabilities: Derivatives 29.0 — 0.3 28.7 29.0 20.3 — 0.1 20.2 20.3 Long-term debt 1,535.5 — 1,790.9 — 1,790.9 1,535.2 — 1,807.4 — 1,807.4 Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions): Alliant Energy Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $8.7 ($32.7 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (35.2 ) (31.4 ) — — Transfers into Level 3 — 0.9 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (6.3 ) (2.1 ) (62.1 ) (17.8 ) Ending balance, March 31 ($32.9 ) ($65.9 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($33.7 ) ($30.0 ) $— $— IPL Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $10.1 ($1.9 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (12.7 ) (7.6 ) — — Transfers into Level 3 — 0.5 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (5.6 ) (3.5 ) (62.1 ) (17.8 ) Ending balance, March 31 ($8.3 ) ($13.1 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($11.4 ) ($6.6 ) $— $— WPL Commodity Contract Derivative Assets and (Liabilities), net Three Months Ended March 31 2017 2016 Beginning balance, January 1 ($1.4 ) ($30.8 ) Total net losses included in changes in net assets (realized/unrealized) (22.5 ) (23.8 ) Transfers into Level 3 — 0.4 Settlements (0.7 ) 1.4 Ending balance, March 31 ($24.6 ) ($52.8 ) The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($22.3 ) ($23.4 ) (a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold. Commodity Contracts - The fair value of electric, natural gas and coal commodity contracts categorized as Level 3 was recognized as net derivative assets (liabilities) as follows (in millions): Alliant Energy IPL WPL Excluding FTRs FTRs Excluding FTRs FTRs Excluding FTRs FTRs March 31, 2017 ($37.0 ) $4.1 ($11.6 ) $3.3 ($25.4 ) $0.8 December 31, 2016 (2.3 ) 11.0 0.1 10.0 (2.4 ) 1.0 |
WPL [Member] | |
Fair Value Measurements | FAIR VALUE MEASUREMENTS Valuation Hierarchy - At each reporting date, Level 1 items included IPL’s 5.1% cumulative preferred stock, Level 2 items included certain non-exchange traded commodity contracts and substantially all of the long-term debt instruments, and Level 3 items included FTRs, certain non-exchange traded commodity contracts and IPL’s deferred proceeds. Fair Value of Financial Instruments - The carrying amounts of current assets and current liabilities approximate fair value because of the short maturity of such financial instruments. Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions): Alliant Energy March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $13.3 $— $1.7 $11.6 $13.3 $41.4 $— $4.6 $36.8 $41.4 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 45.3 — 0.8 44.5 45.3 28.6 — 0.5 28.1 28.6 Long-term debt (including current maturities) 4,320.7 — 4,768.3 2.9 4,771.2 4,320.2 — 4,795.7 3.3 4,799.0 Cumulative preferred stock of IPL 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 IPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $8.8 $— $1.3 $7.5 $8.8 $20.8 $— $2.8 $18.0 $20.8 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 16.3 — 0.5 15.8 16.3 8.3 — 0.4 7.9 8.3 Long-term debt 2,154.0 — 2,342.1 — 2,342.1 2,153.5 — 2,352.3 — 2,352.3 Cumulative preferred stock 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 WPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $4.5 $— $0.4 $4.1 $4.5 $20.6 $— $1.8 $18.8 $20.6 Liabilities: Derivatives 29.0 — 0.3 28.7 29.0 20.3 — 0.1 20.2 20.3 Long-term debt 1,535.5 — 1,790.9 — 1,790.9 1,535.2 — 1,807.4 — 1,807.4 Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions): Alliant Energy Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $8.7 ($32.7 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (35.2 ) (31.4 ) — — Transfers into Level 3 — 0.9 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (6.3 ) (2.1 ) (62.1 ) (17.8 ) Ending balance, March 31 ($32.9 ) ($65.9 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($33.7 ) ($30.0 ) $— $— IPL Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $10.1 ($1.9 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (12.7 ) (7.6 ) — — Transfers into Level 3 — 0.5 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (5.6 ) (3.5 ) (62.1 ) (17.8 ) Ending balance, March 31 ($8.3 ) ($13.1 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($11.4 ) ($6.6 ) $— $— WPL Commodity Contract Derivative Assets and (Liabilities), net Three Months Ended March 31 2017 2016 Beginning balance, January 1 ($1.4 ) ($30.8 ) Total net losses included in changes in net assets (realized/unrealized) (22.5 ) (23.8 ) Transfers into Level 3 — 0.4 Settlements (0.7 ) 1.4 Ending balance, March 31 ($24.6 ) ($52.8 ) The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($22.3 ) ($23.4 ) (a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold. Commodity Contracts - The fair value of electric, natural gas and coal commodity contracts categorized as Level 3 was recognized as net derivative assets (liabilities) as follows (in millions): Alliant Energy IPL WPL Excluding FTRs FTRs Excluding FTRs FTRs Excluding FTRs FTRs March 31, 2017 ($37.0 ) $4.1 ($11.6 ) $3.3 ($25.4 ) $0.8 December 31, 2016 (2.3 ) 11.0 0.1 10.0 (2.4 ) 1.0 |
Derivative Instruments
Derivative Instruments | 3 Months Ended |
Mar. 31, 2017 | |
Derivative Instruments [Line Items] | |
Derivative Instruments | DERIVATIVE INSTRUMENTS Commodity Derivatives - Notional Amounts - As of March 31, 2017 , gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands): Electricity FTRs Natural Gas Coal Diesel Fuel MWhs Years MWhs Years Dths Years Tons Years Gallons Years Alliant Energy 2,304 2017-2018 3,537 2017 160,048 2017-2026 4,113 2017-2019 5,796 2017-2018 IPL — — 2,229 2017 72,924 2017-2026 1,680 2017-2019 — — WPL 2,304 2017-2018 1,308 2017 87,124 2017-2026 2,433 2017-2018 5,796 2017-2018 Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities. The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other liabilities” on the balance sheets as follows (in millions): Alliant Energy IPL WPL Commodity contracts March 31, December 31, March 31, December 31, March 31, December 31, Current derivative assets $12.2 $29.4 $8.2 $19.1 $4.0 $10.3 Non-current derivative assets 1.1 12.0 0.6 1.7 0.5 10.3 Current derivative liabilities 13.4 13.3 2.9 2.7 10.5 10.6 Non-current derivative liabilities 31.9 15.3 13.4 5.6 18.5 9.7 Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At March 31, 2017 and December 31, 2016 , the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered. Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at March 31, 2017 and December 31, 2016 . Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. |
IPL [Member] | |
Derivative Instruments [Line Items] | |
Derivative Instruments | DERIVATIVE INSTRUMENTS Commodity Derivatives - Notional Amounts - As of March 31, 2017 , gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands): Electricity FTRs Natural Gas Coal Diesel Fuel MWhs Years MWhs Years Dths Years Tons Years Gallons Years Alliant Energy 2,304 2017-2018 3,537 2017 160,048 2017-2026 4,113 2017-2019 5,796 2017-2018 IPL — — 2,229 2017 72,924 2017-2026 1,680 2017-2019 — — WPL 2,304 2017-2018 1,308 2017 87,124 2017-2026 2,433 2017-2018 5,796 2017-2018 Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities. The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other liabilities” on the balance sheets as follows (in millions): Alliant Energy IPL WPL Commodity contracts March 31, December 31, March 31, December 31, March 31, December 31, Current derivative assets $12.2 $29.4 $8.2 $19.1 $4.0 $10.3 Non-current derivative assets 1.1 12.0 0.6 1.7 0.5 10.3 Current derivative liabilities 13.4 13.3 2.9 2.7 10.5 10.6 Non-current derivative liabilities 31.9 15.3 13.4 5.6 18.5 9.7 Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At March 31, 2017 and December 31, 2016 , the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered. Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at March 31, 2017 and December 31, 2016 . Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. |
WPL [Member] | |
Derivative Instruments [Line Items] | |
Derivative Instruments | DERIVATIVE INSTRUMENTS Commodity Derivatives - Notional Amounts - As of March 31, 2017 , gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands): Electricity FTRs Natural Gas Coal Diesel Fuel MWhs Years MWhs Years Dths Years Tons Years Gallons Years Alliant Energy 2,304 2017-2018 3,537 2017 160,048 2017-2026 4,113 2017-2019 5,796 2017-2018 IPL — — 2,229 2017 72,924 2017-2026 1,680 2017-2019 — — WPL 2,304 2017-2018 1,308 2017 87,124 2017-2026 2,433 2017-2018 5,796 2017-2018 Financial Statement Presentation - Derivative instruments are recorded at fair value each reporting date on the balance sheets as assets or liabilities. The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other liabilities” on the balance sheets as follows (in millions): Alliant Energy IPL WPL Commodity contracts March 31, December 31, March 31, December 31, March 31, December 31, Current derivative assets $12.2 $29.4 $8.2 $19.1 $4.0 $10.3 Non-current derivative assets 1.1 12.0 0.6 1.7 0.5 10.3 Current derivative liabilities 13.4 13.3 2.9 2.7 10.5 10.6 Non-current derivative liabilities 31.9 15.3 13.4 5.6 18.5 9.7 Credit Risk-related Contingent Features - Various agreements contain credit risk-related contingent features, including requirements to maintain certain credit ratings and/or limitations on liability positions under the agreements based on credit ratings. Certain of these agreements with credit risk-related contingency features are accounted for as derivative instruments. In the event of a material change in creditworthiness or if liability positions exceed certain contractual limits, credit support may need to be provided in the form of letters of credit or cash collateral up to the amount of exposure under the contracts, or the contracts may need to be unwound and underlying liability positions paid. At March 31, 2017 and December 31, 2016 , the aggregate fair value of all derivative instruments with credit risk-related contingent features in a net liability position was not materially different than amounts that would be required to be posted as credit support to counterparties by Alliant Energy, IPL or WPL if the most restrictive credit risk-related contingent features for derivative agreements in a net liability position were triggered. Balance Sheet Offsetting - The fair value amounts of derivative instruments subject to a master netting arrangement are not netted by counterparty on the balance sheets. However, if the fair value amounts of derivative instruments by counterparty were netted, amounts would not be materially different from gross amounts of derivative assets and derivative liabilities at March 31, 2017 and December 31, 2016 . Fair value amounts recognized for the right to reclaim cash collateral (receivable) or the obligation to return cash collateral (payable) are not offset against fair value amounts recognized for derivative instruments executed with the same counterparty under the same master netting arrangement. |
Commitments And Contingencies
Commitments And Contingencies | 3 Months Ended |
Mar. 31, 2017 | |
Commitments and Contingencies Disclosure | COMMITMENTS AND CONTINGENCIES NOTE 12(a) Capital Purchase Obligations - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include the installation of an SCR system at Ottumwa Unit 1 to reduce NOx emissions at the EGU. WPL’s projects include the Riverside expansion, the installation of an SCR system at Columbia Unit 2 to reduce NOx emissions at the EGU, and generation maintenance and performance improvements at Columbia Units 1 and 2. At March 31, 2017 , Alliant Energy’s, IPL’s and WPL’s minimum future commitments related to certain contractual obligations for these projects were $36 million , $5 million and $31 million , respectively. NOTE 12(b) Operating Expense Purchase Obligations - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. Other operating expense purchase obligations with various vendors provide other goods and services. At March 31, 2017 , minimum future commitments related to these operating expense purchase obligations were as follows (in millions): Alliant Energy IPL WPL Purchased power (a) $1,372 $1,266 $106 Natural gas 812 426 386 Coal (b) 165 73 92 Other (c) 38 20 3 $2,387 $1,785 $587 (a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased. (b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of March 31, 2017 regarding expected future usage, which is subject to change. (c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2017 . NOTE 12(c) Legal Proceedings - Flood Damage Claims - In 2013, several plaintiffs purporting to represent a class of residential and commercial property owners filed a complaint against Cedar Rapids and Iowa City Railway Company (CRANDIC), Alliant Energy and various other defendants in the Iowa District Court for Linn County. Plaintiffs assert claims of negligence and strict liability based on their allegations that CRANDIC (along with other defendants) caused or exacerbated flooding of the Cedar River in June 2008. In February 2016, the Iowa District Court for Linn County ruled in favor of Alliant Energy and CRANDIC and dismissed all claims against them, resulting in no loss. In August 2016, the Iowa District Court for Linn County dismissed all claims against the remaining defendants. In September 2016, plaintiffs filed a notice of appeal with the Supreme Court of Iowa. Alliant Energy does not currently believe any material losses for this complaint are both probable and reasonably estimated, and therefore has not recognized any material loss contingency amounts as of March 31, 2017 . NOTE 12(d) Guarantees and Indemnifications - RMT - In 2013, Alliant Energy sold RMT. RMT provided renewable energy services, including construction and high voltage connection services for wind and solar projects. As part of the sale, Alliant Energy indemnified the buyer for any claims, including claims of warranty under the project obligations that were commenced or are based on actions that occurred prior to the sale, except for liabilities already accounted for through adjustments to the purchase price. Alliant Energy also guaranteed RMT’s performance obligations related to certain of RMT’s projects that were commenced prior to Alliant Energy’s sale of RMT. As of March 31, 2017, all warranty periods and performance guarantees expired and all outstanding warranty claims were resolved. Refer to Note 15 for further discussion of RMT, including amounts Alliant Energy recorded to “Operating expenses (income)” during the three months ended March 31, 2017 and 2016 related to certain warranty claims. Whiting Petroleum - In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Whiting Petroleum is an independent oil and gas company. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under general partnership agreements in the oil and gas industry, including with respect to the future abandonment of certain platforms off the coast of California and related onshore plant and equipment owned by the partnerships. The guarantees do not include a maximum limit. As of March 31, 2017 , the present value of the abandonment obligations is estimated at $31 million . Alliant Energy is not aware of any material liabilities related to these guarantees of which it is probable that Alliant Energy Resources, LLC will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of March 31, 2017 . IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the July 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of March 31, 2017 . The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020 . NOTE 12(e) Environmental Matters - Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. Environmental liabilities related to the MGP sites are recorded based upon periodic studies. Such amounts are based on the best current estimate of the remaining amount to be incurred for investigation, remediation and monitoring costs for those sites where the investigation process has been or is substantially completed, and the minimum of the estimated cost range for those sites where the investigation is in its earlier stages. There are inherent uncertainties associated with the estimated remaining costs for MGP projects primarily due to unknown site conditions and potential changes in regulatory agency requirements. It is possible that future cost estimates will be greater than current estimates as the investigation process proceeds and as additional facts become known. Costs of future expenditures for environmental remediation obligations are not discounted. At March 31, 2017 , estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions). At March 31, 2017 , such amounts for WPL were not material. Alliant Energy IPL Range of estimated future costs $12 - $31 $10 - $28 Current and non-current environmental liabilities 17 14 WPL Consent Decree - In 2013, the U.S. District Court for the Western District of Wisconsin approved a Consent Decree that WPL, along with the other owners of Edgewater and Columbia, entered into with the EPA and the Sierra Club, thereby resolving claims against WPL. Such claims included allegations that the owners of Edgewater, Nelson Dewey and Columbia violated the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and the Wisconsin State Implementation Plan designed to implement the CAA. WPL has completed various requirements under the Consent Decree. WPL’s remaining requirements include installing an SCR system at Columbia Unit 2 and fuel switching or retiring Edgewater Unit 4 by December 31, 2018. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits for Columbia Units 1 and 2, and Edgewater Units 4 and 5. In addition, the Consent Decree includes annual plant-wide SO2 and NOx emission caps for Columbia and Edgewater. WPL is in the process of completing approximately $7 million in environmental mitigation projects. Alliant Energy and WPL currently expect to recover material costs incurred by WPL related to compliance with the terms of the Consent Decree from WPL’s electric customers. IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include installing an SCR system or equivalent NOx reduction system at Ottumwa by December 31, 2019; fuel switching or retiring Prairie Creek Unit 4 by June 1, 2018, Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025; and either installing combined cycle technology at, or retiring, Dubuque and Sutherland by June 1, 2019. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits with varying averaging times for Burlington, Lansing, M.L. Kapp, Ottumwa and Prairie Creek. In addition, the Consent Decree includes calendar-year SO2 and NOx emission caps for Prairie Creek, and calendar-year SO2 and NOx emission caps in aggregate for Burlington, Dubuque, Lansing, M.L. Kapp, Ottumwa, Prairie Creek and Sutherland. IPL is in the process of completing approximately $6 million in environmental mitigation projects. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to the environmental control systems and environmental mitigation projects from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Cross-State Air Pollution Rule, Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including carbon emissions from new (CAA Section 111(b)) and existing (CAA Section 111(d)) fossil-fueled EGUs. NOTE 12(f) Collective Bargaining Agreements - At March 31, 2017 , employees covered by collective bargaining agreements represented 56% and 64% of total employees of Alliant Energy and IPL, respectively. In August 2017, IPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 204 (Cedar Rapids) expires, representing 19% and 45% of total employees of Alliant Energy and IPL, respectively. |
IPL [Member] | |
Commitments and Contingencies Disclosure | COMMITMENTS AND CONTINGENCIES NOTE 12(a) Capital Purchase Obligations - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include the installation of an SCR system at Ottumwa Unit 1 to reduce NOx emissions at the EGU. WPL’s projects include the Riverside expansion, the installation of an SCR system at Columbia Unit 2 to reduce NOx emissions at the EGU, and generation maintenance and performance improvements at Columbia Units 1 and 2. At March 31, 2017 , Alliant Energy’s, IPL’s and WPL’s minimum future commitments related to certain contractual obligations for these projects were $36 million , $5 million and $31 million , respectively. NOTE 12(b) Operating Expense Purchase Obligations - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. Other operating expense purchase obligations with various vendors provide other goods and services. At March 31, 2017 , minimum future commitments related to these operating expense purchase obligations were as follows (in millions): Alliant Energy IPL WPL Purchased power (a) $1,372 $1,266 $106 Natural gas 812 426 386 Coal (b) 165 73 92 Other (c) 38 20 3 $2,387 $1,785 $587 (a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased. (b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of March 31, 2017 regarding expected future usage, which is subject to change. (c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2017 . NOTE 12(c) Legal Proceedings - Flood Damage Claims - In 2013, several plaintiffs purporting to represent a class of residential and commercial property owners filed a complaint against Cedar Rapids and Iowa City Railway Company (CRANDIC), Alliant Energy and various other defendants in the Iowa District Court for Linn County. Plaintiffs assert claims of negligence and strict liability based on their allegations that CRANDIC (along with other defendants) caused or exacerbated flooding of the Cedar River in June 2008. In February 2016, the Iowa District Court for Linn County ruled in favor of Alliant Energy and CRANDIC and dismissed all claims against them, resulting in no loss. In August 2016, the Iowa District Court for Linn County dismissed all claims against the remaining defendants. In September 2016, plaintiffs filed a notice of appeal with the Supreme Court of Iowa. Alliant Energy does not currently believe any material losses for this complaint are both probable and reasonably estimated, and therefore has not recognized any material loss contingency amounts as of March 31, 2017 . NOTE 12(d) Guarantees and Indemnifications - RMT - In 2013, Alliant Energy sold RMT. RMT provided renewable energy services, including construction and high voltage connection services for wind and solar projects. As part of the sale, Alliant Energy indemnified the buyer for any claims, including claims of warranty under the project obligations that were commenced or are based on actions that occurred prior to the sale, except for liabilities already accounted for through adjustments to the purchase price. Alliant Energy also guaranteed RMT’s performance obligations related to certain of RMT’s projects that were commenced prior to Alliant Energy’s sale of RMT. As of March 31, 2017, all warranty periods and performance guarantees expired and all outstanding warranty claims were resolved. Refer to Note 15 for further discussion of RMT, including amounts Alliant Energy recorded to “Operating expenses (income)” during the three months ended March 31, 2017 and 2016 related to certain warranty claims. Whiting Petroleum - In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Whiting Petroleum is an independent oil and gas company. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under general partnership agreements in the oil and gas industry, including with respect to the future abandonment of certain platforms off the coast of California and related onshore plant and equipment owned by the partnerships. The guarantees do not include a maximum limit. As of March 31, 2017 , the present value of the abandonment obligations is estimated at $31 million . Alliant Energy is not aware of any material liabilities related to these guarantees of which it is probable that Alliant Energy Resources, LLC will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of March 31, 2017 . IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the July 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of March 31, 2017 . The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020 . NOTE 12(e) Environmental Matters - Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. Environmental liabilities related to the MGP sites are recorded based upon periodic studies. Such amounts are based on the best current estimate of the remaining amount to be incurred for investigation, remediation and monitoring costs for those sites where the investigation process has been or is substantially completed, and the minimum of the estimated cost range for those sites where the investigation is in its earlier stages. There are inherent uncertainties associated with the estimated remaining costs for MGP projects primarily due to unknown site conditions and potential changes in regulatory agency requirements. It is possible that future cost estimates will be greater than current estimates as the investigation process proceeds and as additional facts become known. Costs of future expenditures for environmental remediation obligations are not discounted. At March 31, 2017 , estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions). At March 31, 2017 , such amounts for WPL were not material. Alliant Energy IPL Range of estimated future costs $12 - $31 $10 - $28 Current and non-current environmental liabilities 17 14 WPL Consent Decree - In 2013, the U.S. District Court for the Western District of Wisconsin approved a Consent Decree that WPL, along with the other owners of Edgewater and Columbia, entered into with the EPA and the Sierra Club, thereby resolving claims against WPL. Such claims included allegations that the owners of Edgewater, Nelson Dewey and Columbia violated the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and the Wisconsin State Implementation Plan designed to implement the CAA. WPL has completed various requirements under the Consent Decree. WPL’s remaining requirements include installing an SCR system at Columbia Unit 2 and fuel switching or retiring Edgewater Unit 4 by December 31, 2018. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits for Columbia Units 1 and 2, and Edgewater Units 4 and 5. In addition, the Consent Decree includes annual plant-wide SO2 and NOx emission caps for Columbia and Edgewater. WPL is in the process of completing approximately $7 million in environmental mitigation projects. Alliant Energy and WPL currently expect to recover material costs incurred by WPL related to compliance with the terms of the Consent Decree from WPL’s electric customers. IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include installing an SCR system or equivalent NOx reduction system at Ottumwa by December 31, 2019; fuel switching or retiring Prairie Creek Unit 4 by June 1, 2018, Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025; and either installing combined cycle technology at, or retiring, Dubuque and Sutherland by June 1, 2019. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits with varying averaging times for Burlington, Lansing, M.L. Kapp, Ottumwa and Prairie Creek. In addition, the Consent Decree includes calendar-year SO2 and NOx emission caps for Prairie Creek, and calendar-year SO2 and NOx emission caps in aggregate for Burlington, Dubuque, Lansing, M.L. Kapp, Ottumwa, Prairie Creek and Sutherland. IPL is in the process of completing approximately $6 million in environmental mitigation projects. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to the environmental control systems and environmental mitigation projects from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Cross-State Air Pollution Rule, Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including carbon emissions from new (CAA Section 111(b)) and existing (CAA Section 111(d)) fossil-fueled EGUs. NOTE 12(f) Collective Bargaining Agreements - At March 31, 2017 , employees covered by collective bargaining agreements represented 56% and 64% of total employees of Alliant Energy and IPL, respectively. In August 2017, IPL’s collective bargaining agreement with International Brotherhood of Electrical Workers Local 204 (Cedar Rapids) expires, representing 19% and 45% of total employees of Alliant Energy and IPL, respectively. |
WPL [Member] | |
Commitments and Contingencies Disclosure | COMMITMENTS AND CONTINGENCIES NOTE 12(a) Capital Purchase Obligations - Various contractual obligations contain minimum future commitments related to capital expenditures for certain construction projects. IPL’s projects include the installation of an SCR system at Ottumwa Unit 1 to reduce NOx emissions at the EGU. WPL’s projects include the Riverside expansion, the installation of an SCR system at Columbia Unit 2 to reduce NOx emissions at the EGU, and generation maintenance and performance improvements at Columbia Units 1 and 2. At March 31, 2017 , Alliant Energy’s, IPL’s and WPL’s minimum future commitments related to certain contractual obligations for these projects were $36 million , $5 million and $31 million , respectively. NOTE 12(b) Operating Expense Purchase Obligations - Various commodity supply, transportation and storage contracts help meet obligations to provide electricity and natural gas to utility customers. Other operating expense purchase obligations with various vendors provide other goods and services. At March 31, 2017 , minimum future commitments related to these operating expense purchase obligations were as follows (in millions): Alliant Energy IPL WPL Purchased power (a) $1,372 $1,266 $106 Natural gas 812 426 386 Coal (b) 165 73 92 Other (c) 38 20 3 $2,387 $1,785 $587 (a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased. (b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of March 31, 2017 regarding expected future usage, which is subject to change. (c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2017 . NOTE 12(c) Legal Proceedings - Flood Damage Claims - In 2013, several plaintiffs purporting to represent a class of residential and commercial property owners filed a complaint against Cedar Rapids and Iowa City Railway Company (CRANDIC), Alliant Energy and various other defendants in the Iowa District Court for Linn County. Plaintiffs assert claims of negligence and strict liability based on their allegations that CRANDIC (along with other defendants) caused or exacerbated flooding of the Cedar River in June 2008. In February 2016, the Iowa District Court for Linn County ruled in favor of Alliant Energy and CRANDIC and dismissed all claims against them, resulting in no loss. In August 2016, the Iowa District Court for Linn County dismissed all claims against the remaining defendants. In September 2016, plaintiffs filed a notice of appeal with the Supreme Court of Iowa. Alliant Energy does not currently believe any material losses for this complaint are both probable and reasonably estimated, and therefore has not recognized any material loss contingency amounts as of March 31, 2017 . NOTE 12(d) Guarantees and Indemnifications - RMT - In 2013, Alliant Energy sold RMT. RMT provided renewable energy services, including construction and high voltage connection services for wind and solar projects. As part of the sale, Alliant Energy indemnified the buyer for any claims, including claims of warranty under the project obligations that were commenced or are based on actions that occurred prior to the sale, except for liabilities already accounted for through adjustments to the purchase price. Alliant Energy also guaranteed RMT’s performance obligations related to certain of RMT’s projects that were commenced prior to Alliant Energy’s sale of RMT. As of March 31, 2017, all warranty periods and performance guarantees expired and all outstanding warranty claims were resolved. Refer to Note 15 for further discussion of RMT, including amounts Alliant Energy recorded to “Operating expenses (income)” during the three months ended March 31, 2017 and 2016 related to certain warranty claims. Whiting Petroleum - In 2004, Alliant Energy sold its remaining interest in Whiting Petroleum. Whiting Petroleum is an independent oil and gas company. Alliant Energy Resources, LLC, as the successor to a predecessor entity that owned Whiting Petroleum, and a wholly-owned subsidiary of AEF, continues to guarantee the partnership obligations of an affiliate of Whiting Petroleum under general partnership agreements in the oil and gas industry, including with respect to the future abandonment of certain platforms off the coast of California and related onshore plant and equipment owned by the partnerships. The guarantees do not include a maximum limit. As of March 31, 2017 , the present value of the abandonment obligations is estimated at $31 million . Alliant Energy is not aware of any material liabilities related to these guarantees of which it is probable that Alliant Energy Resources, LLC will be obligated to pay and therefore has not recognized any material liabilities related to this guarantee as of March 31, 2017 . IPL’s Minnesota Electric Distribution Assets - IPL provided indemnifications associated with the July 2015 sale of its Minnesota electric distribution assets for losses resulting from potential breach of IPL’s representations, warranties and obligations under the sale agreement. Alliant Energy and IPL believe the likelihood of having to make any material cash payments under these indemnifications is remote. IPL has not recorded any material liabilities related to these indemnifications as of March 31, 2017 . The general terms of the indemnifications provided by IPL included a maximum limit of $17 million and expire in October 2020 . NOTE 12(e) Environmental Matters - Manufactured Gas Plant (MGP) Sites - IPL and WPL have current or previous ownership interests in various sites that are previously associated with the production of gas for which IPL and WPL have, or may have in the future, liability for investigation, remediation and monitoring costs. IPL and WPL are working pursuant to the requirements of various federal and state agencies to investigate, mitigate, prevent and remediate, where necessary, the environmental impacts to property, including natural resources, at and around these former MGP sites in order to protect public health and the environment. Environmental liabilities related to the MGP sites are recorded based upon periodic studies. Such amounts are based on the best current estimate of the remaining amount to be incurred for investigation, remediation and monitoring costs for those sites where the investigation process has been or is substantially completed, and the minimum of the estimated cost range for those sites where the investigation is in its earlier stages. There are inherent uncertainties associated with the estimated remaining costs for MGP projects primarily due to unknown site conditions and potential changes in regulatory agency requirements. It is possible that future cost estimates will be greater than current estimates as the investigation process proceeds and as additional facts become known. Costs of future expenditures for environmental remediation obligations are not discounted. At March 31, 2017 , estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions). At March 31, 2017 , such amounts for WPL were not material. Alliant Energy IPL Range of estimated future costs $12 - $31 $10 - $28 Current and non-current environmental liabilities 17 14 WPL Consent Decree - In 2013, the U.S. District Court for the Western District of Wisconsin approved a Consent Decree that WPL, along with the other owners of Edgewater and Columbia, entered into with the EPA and the Sierra Club, thereby resolving claims against WPL. Such claims included allegations that the owners of Edgewater, Nelson Dewey and Columbia violated the Prevention of Significant Deterioration program requirements, Title V Operating Permit requirements of the CAA and the Wisconsin State Implementation Plan designed to implement the CAA. WPL has completed various requirements under the Consent Decree. WPL’s remaining requirements include installing an SCR system at Columbia Unit 2 and fuel switching or retiring Edgewater Unit 4 by December 31, 2018. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits for Columbia Units 1 and 2, and Edgewater Units 4 and 5. In addition, the Consent Decree includes annual plant-wide SO2 and NOx emission caps for Columbia and Edgewater. WPL is in the process of completing approximately $7 million in environmental mitigation projects. Alliant Energy and WPL currently expect to recover material costs incurred by WPL related to compliance with the terms of the Consent Decree from WPL’s electric customers. IPL Consent Decree - In 2015, the U.S. District Court for the Northern District of Iowa approved a Consent Decree that IPL entered into with the EPA, the Sierra Club, the State of Iowa and Linn County in Iowa, thereby resolving potential CAA issues associated with emissions from IPL’s coal-fired generating facilities in Iowa. IPL has completed various requirements under the Consent Decree. IPL’s remaining requirements include installing an SCR system or equivalent NOx reduction system at Ottumwa by December 31, 2019; fuel switching or retiring Prairie Creek Unit 4 by June 1, 2018, Burlington by December 31, 2021 and Prairie Creek Units 1 and 3 by December 31, 2025; and either installing combined cycle technology at, or retiring, Dubuque and Sutherland by June 1, 2019. The Consent Decree also establishes SO2, NOx and particulate matter emission rate limits with varying averaging times for Burlington, Lansing, M.L. Kapp, Ottumwa and Prairie Creek. In addition, the Consent Decree includes calendar-year SO2 and NOx emission caps for Prairie Creek, and calendar-year SO2 and NOx emission caps in aggregate for Burlington, Dubuque, Lansing, M.L. Kapp, Ottumwa, Prairie Creek and Sutherland. IPL is in the process of completing approximately $6 million in environmental mitigation projects. Alliant Energy and IPL currently expect to recover material costs incurred by IPL related to the environmental control systems and environmental mitigation projects from IPL’s electric customers. Other Environmental Contingencies - In addition to the environmental liabilities discussed above, various environmental rules are monitored that may have a significant impact on future operations. Several of these environmental rules are subject to legal challenges, reconsideration and/or other uncertainties. Given uncertainties regarding the outcome, timing and compliance plans for these environmental matters, the complete financial impact of each of these rules is not able to be determined; however future capital investments and/or modifications to EGUs to comply with certain of these rules could be significant. Specific current, proposed or potential environmental matters include, among others: Cross-State Air Pollution Rule, Effluent Limitation Guidelines, Coal Combustion Residuals Rule, and various legislation and EPA regulations to monitor and regulate the emission of greenhouse gases, including carbon emissions from new (CAA Section 111(b)) and existing (CAA Section 111(d)) fossil-fueled EGUs. |
Segments Of Business
Segments Of Business | 3 Months Ended |
Mar. 31, 2017 | |
Segment Reporting Information [Line Items] | |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Certain financial information relating to Alliant Energy’s business segments is as follows. Intersegment revenues were not material to Alliant Energy’s operations. Utility (a) Non-Regulated, Alliant Energy Electric Gas Other Total Parent and Other Consolidated (in millions) Three Months Ended March 31, 2017 Operating revenues $677.6 $154.3 $11.7 $843.6 $10.3 $853.9 Operating income 107.2 28.0 0.4 135.6 7.3 142.9 Amounts attributable to Alliant Energy common shareowners: Income from continuing operations, net of tax 89.6 9.4 99.0 Income from discontinued operations, net of tax — 1.4 1.4 Net income 89.6 10.8 100.4 Three Months Ended March 31, 2016 Operating revenues $668.9 $152.2 $13.2 $834.3 $9.5 $843.8 Operating income 109.8 28.8 2.2 140.8 5.1 145.9 Amounts attributable to Alliant Energy common shareowners: Income from continuing operations, net of tax 92.1 5.5 97.6 Loss from discontinued operations, net of tax — (1.1 ) (1.1 ) Net income 92.1 4.4 96.5 (a) Alliant Energy’s utility business segments include: a) utility electric operations, which include Alliant Energy’s entire investment in ATC; b) utility gas operations; and c) utility other, which includes steam operations and the unallocated portions of the utility business. IPL - Certain financial information relating to IPL’s business segments is as follows. Intersegment revenues were not material to IPL’s operations. Electric Gas Other Total (in millions) Three Months Ended March 31, 2017 Operating revenues $356.2 $83.1 $11.2 $450.5 Operating income 33.8 14.4 1.4 49.6 Earnings available for common stock 37.2 Three Months Ended March 31, 2016 Operating revenues $361.6 $84.2 $12.9 $458.7 Operating income 43.4 15.8 2.8 62.0 Earnings available for common stock 45.6 WPL - Certain financial information relating to WPL’s business segments is as follows. Intersegment revenues were not material to WPL’s operations. Electric Gas Other Total (in millions) Three Months Ended March 31, 2017 Operating revenues $321.4 $71.2 $0.5 $393.1 Operating income (loss) 73.4 13.6 (1.0 ) 86.0 Earnings available for common stock 45.5 Three Months Ended March 31, 2016 Operating revenues $307.3 $68.0 $0.3 $375.6 Operating income (loss) 66.4 13.0 (0.6 ) 78.8 Earnings available for common stock 46.5 |
IPL [Member] | |
Segment Reporting Information [Line Items] | |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Certain financial information relating to Alliant Energy’s business segments is as follows. Intersegment revenues were not material to Alliant Energy’s operations. Utility (a) Non-Regulated, Alliant Energy Electric Gas Other Total Parent and Other Consolidated (in millions) Three Months Ended March 31, 2017 Operating revenues $677.6 $154.3 $11.7 $843.6 $10.3 $853.9 Operating income 107.2 28.0 0.4 135.6 7.3 142.9 Amounts attributable to Alliant Energy common shareowners: Income from continuing operations, net of tax 89.6 9.4 99.0 Income from discontinued operations, net of tax — 1.4 1.4 Net income 89.6 10.8 100.4 Three Months Ended March 31, 2016 Operating revenues $668.9 $152.2 $13.2 $834.3 $9.5 $843.8 Operating income 109.8 28.8 2.2 140.8 5.1 145.9 Amounts attributable to Alliant Energy common shareowners: Income from continuing operations, net of tax 92.1 5.5 97.6 Loss from discontinued operations, net of tax — (1.1 ) (1.1 ) Net income 92.1 4.4 96.5 (a) Alliant Energy’s utility business segments include: a) utility electric operations, which include Alliant Energy’s entire investment in ATC; b) utility gas operations; and c) utility other, which includes steam operations and the unallocated portions of the utility business. IPL - Certain financial information relating to IPL’s business segments is as follows. Intersegment revenues were not material to IPL’s operations. Electric Gas Other Total (in millions) Three Months Ended March 31, 2017 Operating revenues $356.2 $83.1 $11.2 $450.5 Operating income 33.8 14.4 1.4 49.6 Earnings available for common stock 37.2 Three Months Ended March 31, 2016 Operating revenues $361.6 $84.2 $12.9 $458.7 Operating income 43.4 15.8 2.8 62.0 Earnings available for common stock 45.6 WPL - Certain financial information relating to WPL’s business segments is as follows. Intersegment revenues were not material to WPL’s operations. Electric Gas Other Total (in millions) Three Months Ended March 31, 2017 Operating revenues $321.4 $71.2 $0.5 $393.1 Operating income (loss) 73.4 13.6 (1.0 ) 86.0 Earnings available for common stock 45.5 Three Months Ended March 31, 2016 Operating revenues $307.3 $68.0 $0.3 $375.6 Operating income (loss) 66.4 13.0 (0.6 ) 78.8 Earnings available for common stock 46.5 |
WPL [Member] | |
Segment Reporting Information [Line Items] | |
Segments Of Business | SEGMENTS OF BUSINESS Alliant Energy - Certain financial information relating to Alliant Energy’s business segments is as follows. Intersegment revenues were not material to Alliant Energy’s operations. Utility (a) Non-Regulated, Alliant Energy Electric Gas Other Total Parent and Other Consolidated (in millions) Three Months Ended March 31, 2017 Operating revenues $677.6 $154.3 $11.7 $843.6 $10.3 $853.9 Operating income 107.2 28.0 0.4 135.6 7.3 142.9 Amounts attributable to Alliant Energy common shareowners: Income from continuing operations, net of tax 89.6 9.4 99.0 Income from discontinued operations, net of tax — 1.4 1.4 Net income 89.6 10.8 100.4 Three Months Ended March 31, 2016 Operating revenues $668.9 $152.2 $13.2 $834.3 $9.5 $843.8 Operating income 109.8 28.8 2.2 140.8 5.1 145.9 Amounts attributable to Alliant Energy common shareowners: Income from continuing operations, net of tax 92.1 5.5 97.6 Loss from discontinued operations, net of tax — (1.1 ) (1.1 ) Net income 92.1 4.4 96.5 (a) Alliant Energy’s utility business segments include: a) utility electric operations, which include Alliant Energy’s entire investment in ATC; b) utility gas operations; and c) utility other, which includes steam operations and the unallocated portions of the utility business. IPL - Certain financial information relating to IPL’s business segments is as follows. Intersegment revenues were not material to IPL’s operations. Electric Gas Other Total (in millions) Three Months Ended March 31, 2017 Operating revenues $356.2 $83.1 $11.2 $450.5 Operating income 33.8 14.4 1.4 49.6 Earnings available for common stock 37.2 Three Months Ended March 31, 2016 Operating revenues $361.6 $84.2 $12.9 $458.7 Operating income 43.4 15.8 2.8 62.0 Earnings available for common stock 45.6 WPL - Certain financial information relating to WPL’s business segments is as follows. Intersegment revenues were not material to WPL’s operations. Electric Gas Other Total (in millions) Three Months Ended March 31, 2017 Operating revenues $321.4 $71.2 $0.5 $393.1 Operating income (loss) 73.4 13.6 (1.0 ) 86.0 Earnings available for common stock 45.5 Three Months Ended March 31, 2016 Operating revenues $307.3 $68.0 $0.3 $375.6 Operating income (loss) 66.4 13.0 (0.6 ) 78.8 Earnings available for common stock 46.5 |
Related Parties
Related Parties | 3 Months Ended |
Mar. 31, 2017 | |
Related Party Transactions [Line Items] | |
Related Parties | RELATED PARTIES Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions): IPL WPL 2017 2016 2017 2016 Corporate Services billings $39 $38 $31 $33 Sales credited 2 1 — 1 Purchases billed 66 96 34 19 Net intercompany payables to Corporate Services were as follows (in millions): IPL WPL March 31, 2017 December 31, 2016 March 31, 2017 December 31, 2016 Net payables to Corporate Services $103 $104 $65 $72 ATC, LLC - Pursuant to various agreements, WPL receives a range of transmission services from ATC, LLC. WPL provides operation, maintenance, and construction services to ATC, LLC. WPL and ATC, LLC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three months ended March 31 were as follows (in millions): 2017 2016 ATC, LLC billings to WPL $26 $27 WPL billings to ATC, LLC 3 3 WPL owed ATC, LLC net amounts of $8 million as of March 31, 2017 and $8 million as of December 31, 2016 . Refer to Note 5(a) for discussion of WPL’s transfer of its investment in ATC, LLC to ATI on December 31, 2016. Franklin County Wind Farm - Refer to Note 3 for discussion of the transfer of the Franklin County wind farm from AEF to IPL in April 2017. |
IPL [Member] | |
Related Party Transactions [Line Items] | |
Related Parties | RELATED PARTIES Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions): IPL WPL 2017 2016 2017 2016 Corporate Services billings $39 $38 $31 $33 Sales credited 2 1 — 1 Purchases billed 66 96 34 19 Net intercompany payables to Corporate Services were as follows (in millions): IPL WPL March 31, 2017 December 31, 2016 March 31, 2017 December 31, 2016 Net payables to Corporate Services $103 $104 $65 $72 ATC, LLC - Pursuant to various agreements, WPL receives a range of transmission services from ATC, LLC. WPL provides operation, maintenance, and construction services to ATC, LLC. WPL and ATC, LLC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three months ended March 31 were as follows (in millions): 2017 2016 ATC, LLC billings to WPL $26 $27 WPL billings to ATC, LLC 3 3 WPL owed ATC, LLC net amounts of $8 million as of March 31, 2017 and $8 million as of December 31, 2016 . Refer to Note 5(a) for discussion of WPL’s transfer of its investment in ATC, LLC to ATI on December 31, 2016. Franklin County Wind Farm - Refer to Note 3 for discussion of the transfer of the Franklin County wind farm from AEF to IPL in April 2017. |
WPL [Member] | |
Related Party Transactions [Line Items] | |
Related Parties | RELATED PARTIES Service Agreements - Pursuant to service agreements, IPL and WPL receive various administrative and general services from an affiliate, Corporate Services. These services are billed to IPL and WPL at cost based on expenses incurred by Corporate Services for the benefit of IPL and WPL, respectively. These costs consisted primarily of employee compensation and benefits, fees associated with various professional services, depreciation and amortization of property, plant and equipment, and a return on net assets. Corporate Services also acts as agent on behalf of IPL and WPL pursuant to the service agreements. As agent, Corporate Services enters into energy, capacity, ancillary services, and transmission sale and purchase transactions within MISO. Corporate Services assigns such sales and purchases among IPL and WPL based on statements received from MISO. The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions): IPL WPL 2017 2016 2017 2016 Corporate Services billings $39 $38 $31 $33 Sales credited 2 1 — 1 Purchases billed 66 96 34 19 Net intercompany payables to Corporate Services were as follows (in millions): IPL WPL March 31, 2017 December 31, 2016 March 31, 2017 December 31, 2016 Net payables to Corporate Services $103 $104 $65 $72 ATC, LLC - Pursuant to various agreements, WPL receives a range of transmission services from ATC, LLC. WPL provides operation, maintenance, and construction services to ATC, LLC. WPL and ATC, LLC also bill each other for use of shared facilities owned by each party. The related amounts billed between the parties for the three months ended March 31 were as follows (in millions): 2017 2016 ATC, LLC billings to WPL $26 $27 WPL billings to ATC, LLC 3 3 WPL owed ATC, LLC net amounts of $8 million as of March 31, 2017 and $8 million as of December 31, 2016 . Refer to Note 5(a) for discussion of WPL’s transfer of its investment in ATC, LLC to ATI on December 31, 2016. |
Discontinued Operations
Discontinued Operations | 3 Months Ended |
Mar. 31, 2017 | |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | |
Discontinued Operations and Assets and Liabilities Held For Sale | DISCONTINUED OPERATIONS In 2013, Alliant Energy sold RMT to narrow its strategic focus and risk profile. The operating results of RMT have been separately classified and reported as discontinued operations in Alliant Energy’s income statements. A summary of the components of discontinued operations in Alliant Energy’s income statements for the three months ended March 31 was as follows (in millions): 2017 2016 Operating expenses (income) ($2.3 ) $1.9 Income (loss) before income taxes 2.3 (1.9 ) Income tax expense (benefit) 0.9 (0.8 ) Income (loss) from discontinued operations, net of tax $1.4 ($1.1 ) Refer to Note 12(d) for further discussion of warranty claims associated with RMT that have resulted in operating expenses and income subsequent to the sale. |
Summary Of Significant Accoun21
Summary Of Significant Accounting Policies (Policy) | 3 Months Ended |
Mar. 31, 2017 | |
General, Basis of Accounting | The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K. |
General, Use of Estimates | In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the three months ended March 31, 2017 are not necessarily indicative of results that may be expected for the year ending December 31, 2017 . A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. |
General, Reclassification | Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes. Unless otherwise noted, the Notes herein exclude discontinued operations for all periods presented. As required by GAAP, all prior period financial statements and disclosures presented herein, including all Alliant Energy share and per share amounts, have been restated to reflect a two -for-one common stock split distributed in May 2016. |
New Accounting Standards | New Accounting Standards - Revenue Recognition - In May 2014, the Financial Accounting Standards Board issued an accounting standard providing principles for recognizing revenue for the transfer of promised goods or services to customers with the consideration to which the entity expects to be entitled in exchange for those goods or services. This standard also requires disclosures about the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard can be applied retrospectively to all prior reporting periods presented, or retrospectively with a cumulative effect to the opening retained earnings balance on January 1, 2018 . Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations and do not anticipate a significant change in revenue recognition for retail electric and gas sales, which represent the majority of Alliant Energy’s, IPL’s and WPL’s revenues. Alliant Energy, IPL and WPL continue to evaluate additional impacts of this standard, as well as which transition method will be utilized. Leases - In February 2016, the Financial Accounting Standards Board issued an accounting standard requiring lease assets and lease liabilities, including operating leases, to be recognized on the balance sheet for all leases with terms longer than 12 months. The standard also requires disclosure of key information about leasing arrangements. Alliant Energy, IPL and WPL currently expect to adopt this standard on January 1, 2019 and are evaluating the impact of this standard on their financial condition and results of operations and expect an increase in assets and liabilities from recognizing operating leases on their balance sheets. Presentation of Net Periodic Pension and Postretirement Benefit Costs - In March 2017, the Financial Accounting Standards Board issued an accounting standard amending the income statement presentation of the components of net periodic benefit costs for defined benefit pension and other postretirement plans. The standard requires entities to (1) disaggregate the current service cost component from the other components of net periodic benefit costs and present it with other employee compensation costs in the income statement; and (2) include the other components in the income statement outside of operating income. In addition, only the service cost component of net periodic benefit costs is eligible for capitalization into property, plant and equipment, when applicable. IPL and WPL, as rate-regulated entities, currently expect to capitalize the other components of net periodic benefit costs into regulatory assets or regulatory liabilities, when applicable in accordance with regulations by FERC and various state regulatory commissions. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard must be applied retrospectively for the presentation requirements and prospectively for the capitalization requirements. Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations. |
IPL [Member] | |
General, Basis of Accounting | The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K. |
General, Use of Estimates | In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the three months ended March 31, 2017 are not necessarily indicative of results that may be expected for the year ending December 31, 2017 . A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. |
General, Reclassification | Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes. Unless otherwise noted, the Notes herein exclude discontinued operations for all periods presented. As required by GAAP, all prior period financial statements and disclosures presented herein, including all Alliant Energy share and per share amounts, have been restated to reflect a two -for-one common stock split distributed in May 2016. |
New Accounting Standards | New Accounting Standards - Revenue Recognition - In May 2014, the Financial Accounting Standards Board issued an accounting standard providing principles for recognizing revenue for the transfer of promised goods or services to customers with the consideration to which the entity expects to be entitled in exchange for those goods or services. This standard also requires disclosures about the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard can be applied retrospectively to all prior reporting periods presented, or retrospectively with a cumulative effect to the opening retained earnings balance on January 1, 2018 . Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations and do not anticipate a significant change in revenue recognition for retail electric and gas sales, which represent the majority of Alliant Energy’s, IPL’s and WPL’s revenues. Alliant Energy, IPL and WPL continue to evaluate additional impacts of this standard, as well as which transition method will be utilized. Leases - In February 2016, the Financial Accounting Standards Board issued an accounting standard requiring lease assets and lease liabilities, including operating leases, to be recognized on the balance sheet for all leases with terms longer than 12 months. The standard also requires disclosure of key information about leasing arrangements. Alliant Energy, IPL and WPL currently expect to adopt this standard on January 1, 2019 and are evaluating the impact of this standard on their financial condition and results of operations and expect an increase in assets and liabilities from recognizing operating leases on their balance sheets. Presentation of Net Periodic Pension and Postretirement Benefit Costs - In March 2017, the Financial Accounting Standards Board issued an accounting standard amending the income statement presentation of the components of net periodic benefit costs for defined benefit pension and other postretirement plans. The standard requires entities to (1) disaggregate the current service cost component from the other components of net periodic benefit costs and present it with other employee compensation costs in the income statement; and (2) include the other components in the income statement outside of operating income. In addition, only the service cost component of net periodic benefit costs is eligible for capitalization into property, plant and equipment, when applicable. IPL and WPL, as rate-regulated entities, currently expect to capitalize the other components of net periodic benefit costs into regulatory assets or regulatory liabilities, when applicable in accordance with regulations by FERC and various state regulatory commissions. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard must be applied retrospectively for the presentation requirements and prospectively for the capitalization requirements. Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations. |
WPL [Member] | |
General, Basis of Accounting | The interim unaudited Financial Statements included herein have been prepared pursuant to the rules and regulations of the Securities and Exchange Commission. Accordingly, certain information and note disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted, although management believes that the disclosures are adequate to make the information presented not misleading. These Financial Statements should be read in conjunction with the financial statements and the notes thereto included in the latest combined Annual Report on Form 10-K. |
General, Use of Estimates | In the opinion of management, all adjustments, which unless otherwise noted are normal and recurring in nature, necessary for a fair presentation of the results of operations, financial position and cash flows have been made. Results for the three months ended March 31, 2017 are not necessarily indicative of results that may be expected for the year ending December 31, 2017 . A change in management’s estimates or assumptions could have a material impact on financial condition and results of operations during the period in which such change occurred. |
General, Reclassification | Certain prior period amounts in the Financial Statements and Notes have been reclassified to conform to the current period presentation for comparative purposes. Unless otherwise noted, the Notes herein exclude discontinued operations for all periods presented. As required by GAAP, all prior period financial statements and disclosures presented herein, including all Alliant Energy share and per share amounts, have been restated to reflect a two -for-one common stock split distributed in May 2016. |
New Accounting Standards | New Accounting Standards - Revenue Recognition - In May 2014, the Financial Accounting Standards Board issued an accounting standard providing principles for recognizing revenue for the transfer of promised goods or services to customers with the consideration to which the entity expects to be entitled in exchange for those goods or services. This standard also requires disclosures about the nature, amount, timing and uncertainty of revenue and cash flows arising from contracts with customers. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard can be applied retrospectively to all prior reporting periods presented, or retrospectively with a cumulative effect to the opening retained earnings balance on January 1, 2018 . Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations and do not anticipate a significant change in revenue recognition for retail electric and gas sales, which represent the majority of Alliant Energy’s, IPL’s and WPL’s revenues. Alliant Energy, IPL and WPL continue to evaluate additional impacts of this standard, as well as which transition method will be utilized. Leases - In February 2016, the Financial Accounting Standards Board issued an accounting standard requiring lease assets and lease liabilities, including operating leases, to be recognized on the balance sheet for all leases with terms longer than 12 months. The standard also requires disclosure of key information about leasing arrangements. Alliant Energy, IPL and WPL currently expect to adopt this standard on January 1, 2019 and are evaluating the impact of this standard on their financial condition and results of operations and expect an increase in assets and liabilities from recognizing operating leases on their balance sheets. Presentation of Net Periodic Pension and Postretirement Benefit Costs - In March 2017, the Financial Accounting Standards Board issued an accounting standard amending the income statement presentation of the components of net periodic benefit costs for defined benefit pension and other postretirement plans. The standard requires entities to (1) disaggregate the current service cost component from the other components of net periodic benefit costs and present it with other employee compensation costs in the income statement; and (2) include the other components in the income statement outside of operating income. In addition, only the service cost component of net periodic benefit costs is eligible for capitalization into property, plant and equipment, when applicable. IPL and WPL, as rate-regulated entities, currently expect to capitalize the other components of net periodic benefit costs into regulatory assets or regulatory liabilities, when applicable in accordance with regulations by FERC and various state regulatory commissions. Alliant Energy, IPL and WPL will adopt this standard on January 1, 2018. Upon adoption, the standard must be applied retrospectively for the presentation requirements and prospectively for the capitalization requirements. Alliant Energy, IPL and WPL are currently evaluating the impact of this standard on their financial condition and results of operations. |
Regulatory Matters (Tables)
Regulatory Matters (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Regulatory Assets [Line Items] | |
Regulatory Assets | Regulatory assets were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Tax-related $1,080.2 $1,055.6 $1,044.9 $1,022.4 $35.3 $33.2 Pension and OPEB costs 568.5 578.7 289.1 294.0 279.4 284.7 Asset retirement obligations 108.6 105.9 67.1 64.3 41.5 41.6 Derivatives 46.4 30.7 17.2 10.0 29.2 20.7 WPL’s EGUs retired early 39.7 41.4 — — 39.7 41.4 Emission allowances 26.0 26.2 26.0 26.2 — — Other 93.6 76.6 56.5 41.9 37.1 34.7 $1,963.0 $1,915.1 $1,500.8 $1,458.8 $462.2 $456.3 |
Regulatory Liabilities | Regulatory liabilities were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Cost of removal obligations $413.0 $411.6 $271.1 $269.4 $141.9 $142.2 Electric transmission cost recovery 128.3 72.0 75.9 35.7 52.4 36.3 IPL’s tax benefit riders 64.7 83.5 64.7 83.5 — — Commodity cost recovery 32.9 30.8 20.1 17.8 12.8 13.0 Energy efficiency cost recovery 20.6 20.5 — — 20.6 20.5 Derivatives 9.0 31.5 5.1 12.1 3.9 19.4 Other 28.1 31.1 11.4 12.3 16.7 18.8 $696.6 $681.0 $448.3 $430.8 $248.3 $250.2 |
Tax Benefit Riders | For the three months ended March 31 , 2017 , Alliant Energy’s and IPL’s “IPL’s tax benefit riders” regulatory liabilities decreased by $19 million as follows (in millions): Electric tax benefit rider credits $17 Gas tax benefit rider credits 2 $19 |
IPL [Member] | |
Regulatory Assets [Line Items] | |
Regulatory Assets | Regulatory assets were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Tax-related $1,080.2 $1,055.6 $1,044.9 $1,022.4 $35.3 $33.2 Pension and OPEB costs 568.5 578.7 289.1 294.0 279.4 284.7 Asset retirement obligations 108.6 105.9 67.1 64.3 41.5 41.6 Derivatives 46.4 30.7 17.2 10.0 29.2 20.7 WPL’s EGUs retired early 39.7 41.4 — — 39.7 41.4 Emission allowances 26.0 26.2 26.0 26.2 — — Other 93.6 76.6 56.5 41.9 37.1 34.7 $1,963.0 $1,915.1 $1,500.8 $1,458.8 $462.2 $456.3 |
Regulatory Liabilities | Regulatory liabilities were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Cost of removal obligations $413.0 $411.6 $271.1 $269.4 $141.9 $142.2 Electric transmission cost recovery 128.3 72.0 75.9 35.7 52.4 36.3 IPL’s tax benefit riders 64.7 83.5 64.7 83.5 — — Commodity cost recovery 32.9 30.8 20.1 17.8 12.8 13.0 Energy efficiency cost recovery 20.6 20.5 — — 20.6 20.5 Derivatives 9.0 31.5 5.1 12.1 3.9 19.4 Other 28.1 31.1 11.4 12.3 16.7 18.8 $696.6 $681.0 $448.3 $430.8 $248.3 $250.2 |
Tax Benefit Riders | For the three months ended March 31 , 2017 , Alliant Energy’s and IPL’s “IPL’s tax benefit riders” regulatory liabilities decreased by $19 million as follows (in millions): Electric tax benefit rider credits $17 Gas tax benefit rider credits 2 $19 |
WPL [Member] | |
Regulatory Assets [Line Items] | |
Regulatory Assets | Regulatory assets were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Tax-related $1,080.2 $1,055.6 $1,044.9 $1,022.4 $35.3 $33.2 Pension and OPEB costs 568.5 578.7 289.1 294.0 279.4 284.7 Asset retirement obligations 108.6 105.9 67.1 64.3 41.5 41.6 Derivatives 46.4 30.7 17.2 10.0 29.2 20.7 WPL’s EGUs retired early 39.7 41.4 — — 39.7 41.4 Emission allowances 26.0 26.2 26.0 26.2 — — Other 93.6 76.6 56.5 41.9 37.1 34.7 $1,963.0 $1,915.1 $1,500.8 $1,458.8 $462.2 $456.3 |
Regulatory Liabilities | Regulatory liabilities were comprised of the following items (in millions): Alliant Energy IPL WPL March 31, December 31, March 31, December 31, March 31, December 31, Cost of removal obligations $413.0 $411.6 $271.1 $269.4 $141.9 $142.2 Electric transmission cost recovery 128.3 72.0 75.9 35.7 52.4 36.3 IPL’s tax benefit riders 64.7 83.5 64.7 83.5 — — Commodity cost recovery 32.9 30.8 20.1 17.8 12.8 13.0 Energy efficiency cost recovery 20.6 20.5 — — 20.6 20.5 Derivatives 9.0 31.5 5.1 12.1 3.9 19.4 Other 28.1 31.1 11.4 12.3 16.7 18.8 $696.6 $681.0 $448.3 $430.8 $248.3 $250.2 |
Receivables (Tables)
Receivables (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Receivables [Line Items] | |
Maximum And Average Outstanding Cash Proceeds | IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three months ended March 31 were as follows (in millions): 2017 2016 Maximum outstanding aggregate cash proceeds $79.0 $75.0 Average outstanding aggregate cash proceeds 38.4 39.1 |
Receivables Sold Under The Receivables Agreement | The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions): March 31, 2017 December 31, 2016 Customer accounts receivable $143.7 $157.6 Unbilled utility revenues 76.8 90.4 Other receivables 0.5 0.1 Receivables sold to third party 221.0 248.1 Less: cash proceeds (a) 56.0 21.0 Deferred proceeds 165.0 227.1 Less: allowance for doubtful accounts 16.0 16.0 Fair value of deferred proceeds $149.0 $211.1 (a) Changes in cash proceeds are presented in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s cash flows statements. |
Additional Attributes Of Receivables Sold Under The Receivables Agreement | Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three months ended March 31 were as follows (in millions): 2017 2016 Collections reinvested in receivables $501.2 $440.2 Write-offs, net of recoveries 4.6 0.4 |
IPL [Member] | |
Receivables [Line Items] | |
Maximum And Average Outstanding Cash Proceeds | IPL’s maximum and average outstanding cash proceeds (based on daily outstanding balances) related to the sales of accounts receivable program for the three months ended March 31 were as follows (in millions): 2017 2016 Maximum outstanding aggregate cash proceeds $79.0 $75.0 Average outstanding aggregate cash proceeds 38.4 39.1 |
Receivables Sold Under The Receivables Agreement | The attributes of IPL’s receivables sold under the Receivables Agreement were as follows (in millions): March 31, 2017 December 31, 2016 Customer accounts receivable $143.7 $157.6 Unbilled utility revenues 76.8 90.4 Other receivables 0.5 0.1 Receivables sold to third party 221.0 248.1 Less: cash proceeds (a) 56.0 21.0 Deferred proceeds 165.0 227.1 Less: allowance for doubtful accounts 16.0 16.0 Fair value of deferred proceeds $149.0 $211.1 (a) Changes in cash proceeds are presented in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s cash flows statements. |
Additional Attributes Of Receivables Sold Under The Receivables Agreement | Additional attributes of IPL’s receivables sold under the Receivables Agreement for the three months ended March 31 were as follows (in millions): 2017 2016 Collections reinvested in receivables $501.2 $440.2 Write-offs, net of recoveries 4.6 0.4 |
Investments (Tables)
Investments (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Schedule of Investments [Line Items] | |
Unconsolidated Equity Investments | Equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions): Alliant Energy WPL 2017 2016 2017 2016 ATC Investment ($11.5 ) ($10.7 ) $— ($10.7 ) Other — 0.2 — — ($11.5 ) ($10.5 ) $— ($10.7 ) |
WPL [Member] | |
Schedule of Investments [Line Items] | |
Unconsolidated Equity Investments | Equity (income) loss from unconsolidated investments accounted for under the equity method of accounting for the three months ended March 31 was as follows (in millions): Alliant Energy WPL 2017 2016 2017 2016 ATC Investment ($11.5 ) ($10.7 ) $— ($10.7 ) Other — 0.2 — — ($11.5 ) ($10.5 ) $— ($10.7 ) |
Common Equity (Tables)
Common Equity (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Stockholders' Equity Note [Abstract] | |
Common Share Activity | A summary of Alliant Energy’s common stock activity was as follows: Shares outstanding, January 1, 2017 227,673,654 Shareowner Direct Plan issuances 190,286 Equity-based compensation plans ( Note 9(b) ) 5,185 Other (45,847 ) Shares outstanding, March 31, 2017 227,823,278 |
Debt (Tables)
Debt (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Debt Disclosure [Line Items] | |
Other Short-Term Borrowings | Information regarding commercial paper classified as short-term debt was as follows (dollars in millions): Alliant Energy Parent March 31, 2017 (Consolidated) Company IPL WPL Commercial paper outstanding $302.8 $202.4 $9.2 $91.2 Commercial paper weighted average interest rates 1.1% 1.2% 1.2% 0.9% Available credit facility capacity $697.2 $97.6 $290.8 $308.8 Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Maximum amount outstanding (based on daily outstanding balances) $325.5 $242.6 $9.2 $— $113.6 $55.7 Average amount outstanding (based on daily outstanding balances) $276.5 $199.0 $0.1 $— $79.1 $25.8 Weighted average interest rates 0.9% 0.6% 1.1% N/A 0.7% 0.4% |
IPL [Member] | |
Debt Disclosure [Line Items] | |
Other Short-Term Borrowings | Information regarding commercial paper classified as short-term debt was as follows (dollars in millions): Alliant Energy Parent March 31, 2017 (Consolidated) Company IPL WPL Commercial paper outstanding $302.8 $202.4 $9.2 $91.2 Commercial paper weighted average interest rates 1.1% 1.2% 1.2% 0.9% Available credit facility capacity $697.2 $97.6 $290.8 $308.8 Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Maximum amount outstanding (based on daily outstanding balances) $325.5 $242.6 $9.2 $— $113.6 $55.7 Average amount outstanding (based on daily outstanding balances) $276.5 $199.0 $0.1 $— $79.1 $25.8 Weighted average interest rates 0.9% 0.6% 1.1% N/A 0.7% 0.4% |
WPL [Member] | |
Debt Disclosure [Line Items] | |
Other Short-Term Borrowings | Information regarding commercial paper classified as short-term debt was as follows (dollars in millions): Alliant Energy Parent March 31, 2017 (Consolidated) Company IPL WPL Commercial paper outstanding $302.8 $202.4 $9.2 $91.2 Commercial paper weighted average interest rates 1.1% 1.2% 1.2% 0.9% Available credit facility capacity $697.2 $97.6 $290.8 $308.8 Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Maximum amount outstanding (based on daily outstanding balances) $325.5 $242.6 $9.2 $— $113.6 $55.7 Average amount outstanding (based on daily outstanding balances) $276.5 $199.0 $0.1 $— $79.1 $25.8 Weighted average interest rates 0.9% 0.6% 1.1% N/A 0.7% 0.4% |
Income Taxes (Tables)
Income Taxes (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Income Taxes [Line Items] | |
Schedule Of Effective Income Tax Rates | The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes. Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % IPL’s tax benefit riders (7.8 ) (8.7 ) (19.4 ) (20.7 ) — — Effect of rate-making on property-related differences (7.5 ) (6.8 ) (17.9 ) (15.2 ) (1.7 ) (0.8 ) Production tax credits (5.9 ) (6.3 ) (6.6 ) (6.7 ) (7.0 ) (6.5 ) Other items, net 1.0 4.5 (1.3 ) 5.9 4.7 4.8 Overall income tax rate 14.8 % 17.7 % (10.2 %) (1.7 %) 31.0 % 32.5 % |
Summary Of Tax Credit Carryforwards | At March 31, 2017 , carryforwards and expiration dates were estimated as follows (in millions): Range of Expiration Dates Alliant Energy IPL WPL Federal net operating losses 2030-2037 $633 $315 $217 State net operating losses 2018-2037 696 13 2 Federal tax credits 2022-2037 284 104 118 |
IPL [Member] | |
Income Taxes [Line Items] | |
Schedule Of Effective Income Tax Rates | The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes. Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % IPL’s tax benefit riders (7.8 ) (8.7 ) (19.4 ) (20.7 ) — — Effect of rate-making on property-related differences (7.5 ) (6.8 ) (17.9 ) (15.2 ) (1.7 ) (0.8 ) Production tax credits (5.9 ) (6.3 ) (6.6 ) (6.7 ) (7.0 ) (6.5 ) Other items, net 1.0 4.5 (1.3 ) 5.9 4.7 4.8 Overall income tax rate 14.8 % 17.7 % (10.2 %) (1.7 %) 31.0 % 32.5 % |
Summary Of Tax Credit Carryforwards | At March 31, 2017 , carryforwards and expiration dates were estimated as follows (in millions): Range of Expiration Dates Alliant Energy IPL WPL Federal net operating losses 2030-2037 $633 $315 $217 State net operating losses 2018-2037 696 13 2 Federal tax credits 2022-2037 284 104 118 |
WPL [Member] | |
Income Taxes [Line Items] | |
Schedule Of Effective Income Tax Rates | The overall income tax rates shown in the following table were computed by dividing income tax expense (benefit) by income from continuing operations before income taxes. Alliant Energy IPL WPL Three Months Ended March 31 2017 2016 2017 2016 2017 2016 Statutory federal income tax rate 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % 35.0 % IPL’s tax benefit riders (7.8 ) (8.7 ) (19.4 ) (20.7 ) — — Effect of rate-making on property-related differences (7.5 ) (6.8 ) (17.9 ) (15.2 ) (1.7 ) (0.8 ) Production tax credits (5.9 ) (6.3 ) (6.6 ) (6.7 ) (7.0 ) (6.5 ) Other items, net 1.0 4.5 (1.3 ) 5.9 4.7 4.8 Overall income tax rate 14.8 % 17.7 % (10.2 %) (1.7 %) 31.0 % 32.5 % |
Summary Of Tax Credit Carryforwards | At March 31, 2017 , carryforwards and expiration dates were estimated as follows (in millions): Range of Expiration Dates Alliant Energy IPL WPL Federal net operating losses 2030-2037 $633 $315 $217 State net operating losses 2018-2037 696 13 2 Federal tax credits 2022-2037 284 104 118 |
Benefit Plans (Tables)
Benefit Plans (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Defined Benefit Plan Disclosure [Line Items] | |
Defined Benefit Pension And Other Postretirement Benefits Plans | The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three months ended March 31 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans amounts represent those respective amounts for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans amounts represent respective amounts for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan. Defined Benefit Pension Plans OPEB Plans Alliant Energy 2017 2016 2017 2016 Service cost $3.1 $3.2 $1.2 $1.3 Interest cost 12.8 13.3 2.2 2.3 Expected return on plan assets (16.4 ) (16.4 ) (1.5 ) (1.5 ) Amortization of prior service credit (0.1 ) (0.1 ) (0.1 ) (1.0 ) Amortization of actuarial loss 9.4 9.3 1.0 1.2 $8.8 $9.3 $2.8 $2.3 Defined Benefit Pension Plans OPEB Plans IPL 2017 2016 2017 2016 Service cost $1.8 $1.9 $0.5 $0.6 Interest cost 5.9 6.1 0.9 1.0 Expected return on plan assets (7.7 ) (7.7 ) (1.1 ) (1.0 ) Amortization of prior service credit — — — (0.7 ) Amortization of actuarial loss 4.0 4.1 0.5 0.6 $4.0 $4.4 $0.8 $0.5 Defined Benefit Pension Plans OPEB Plans WPL 2017 2016 2017 2016 Service cost $1.2 $1.2 $0.5 $0.5 Interest cost 5.5 5.6 0.9 0.9 Expected return on plan assets (7.1 ) (7.1 ) (0.2 ) (0.2 ) Amortization of prior service cost (credit) — 0.1 (0.1 ) (0.2 ) Amortization of actuarial loss 4.6 4.4 0.4 0.5 $4.2 $4.2 $1.5 $1.5 |
Employees Participate In Defined Contribution Retirement Plans | For the three months ended March 31 , costs related to the 401(k) savings plan, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 401(k) costs $6.5 $6.2 $3.4 $3.1 $2.9 $2.8 |
Recognized Compensation Expense And Income Tax Benefits | A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three months ended March 31 was as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 Compensation expense $3.2 $5.3 $1.7 $2.8 $1.4 $2.3 Income tax benefits 1.3 2.2 0.7 1.1 0.5 0.9 |
Performance Shares and Performance Units [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Schedule Of Equity-based Compensation Plans Activity | A summary of the performance shares and performance units activity, with amounts representing the target number of awards, was as follows: Performance Shares Performance Units 2017 2016 2017 2016 Nonvested awards, January 1 257,599 288,430 93,320 116,412 Granted 63,804 67,552 21,558 23,918 Vested (99,438 ) (98,186 ) (37,395 ) (42,760 ) Forfeited — (1,230 ) (497 ) (764 ) Nonvested awards, March 31 221,965 256,566 76,986 96,806 Vested Awards - During the three months ended March 31 , certain performance shares and performance units vested, resulting in payouts (a combination of cash and common stock for the performance shares and cash only for the performance units) as follows: Performance Shares Performance Units 2017 2016 2017 2016 2014 Grant 2013 Grant 2014 Grant 2013 Grant Performance awards vested 99,438 98,186 37,395 42,760 Percentage of target number of performance awards 147.5 % 165.0 % 147.5 % 165.0 % Aggregate payout value (in millions) $5.6 $5.1 $1.5 $1.7 Payout - cash (in millions) $5.1 $2.9 $1.5 $1.7 Payout - common stock shares issued 5,185 22,408 N/A N/A Fair Value of Awards - Information related to fair values of nonvested performance shares and performance units at March 31, 2017 , by year of grant, was as follows: Performance Shares Performance Units 2017 Grant 2016 Grant 2015 Grant 2017 Grant 2016 Grant 2015 Grant Nonvested awards at target 63,804 67,355 90,806 21,061 22,657 33,268 Alliant Energy common stock closing price on March 31, 2017 $39.61 $39.61 $39.61 $39.61 $39.61 N/A Alliant Energy common stock closing price on grant date N/A N/A N/A N/A N/A $32.55 Estimated payout percentage based on performance criteria 100 % 160 % 130 % 100 % 160 % 130 % Fair values of each nonvested award $39.61 $63.38 $51.49 $39.61 $63.38 $42.32 |
Performance Restricted Stock Unit [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Schedule Of Equity-based Compensation Plans Activity | A summary of the performance restricted stock units activity, with amounts representing the target number of units, was as follows: 2017 2016 Units Weighted Average Grant Date Fair Value Units Weighted Average Grant Date Fair Value Nonvested units, January 1 67,355 $33.96 — $— Granted 63,804 39.11 67,552 33.93 Forfeited — — (1,230 ) 33.90 Nonvested units, March 31 131,159 36.46 66,322 33.93 |
Restricted Stock Unit [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Schedule Of Equity-based Compensation Plans Activity | A summary of the restricted stock units activity was as follows: 2017 2016 Nonvested units, January 1 57,736 — Granted 54,688 57,904 Forfeited — (1,054 ) Nonvested units, March 31 112,424 56,850 |
IPL [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Defined Benefit Pension And Other Postretirement Benefits Plans | The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three months ended March 31 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans amounts represent those respective amounts for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans amounts represent respective amounts for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan. Defined Benefit Pension Plans OPEB Plans Alliant Energy 2017 2016 2017 2016 Service cost $3.1 $3.2 $1.2 $1.3 Interest cost 12.8 13.3 2.2 2.3 Expected return on plan assets (16.4 ) (16.4 ) (1.5 ) (1.5 ) Amortization of prior service credit (0.1 ) (0.1 ) (0.1 ) (1.0 ) Amortization of actuarial loss 9.4 9.3 1.0 1.2 $8.8 $9.3 $2.8 $2.3 Defined Benefit Pension Plans OPEB Plans IPL 2017 2016 2017 2016 Service cost $1.8 $1.9 $0.5 $0.6 Interest cost 5.9 6.1 0.9 1.0 Expected return on plan assets (7.7 ) (7.7 ) (1.1 ) (1.0 ) Amortization of prior service credit — — — (0.7 ) Amortization of actuarial loss 4.0 4.1 0.5 0.6 $4.0 $4.4 $0.8 $0.5 Defined Benefit Pension Plans OPEB Plans WPL 2017 2016 2017 2016 Service cost $1.2 $1.2 $0.5 $0.5 Interest cost 5.5 5.6 0.9 0.9 Expected return on plan assets (7.1 ) (7.1 ) (0.2 ) (0.2 ) Amortization of prior service cost (credit) — 0.1 (0.1 ) (0.2 ) Amortization of actuarial loss 4.6 4.4 0.4 0.5 $4.2 $4.2 $1.5 $1.5 |
Employees Participate In Defined Contribution Retirement Plans | For the three months ended March 31 , costs related to the 401(k) savings plan, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 401(k) costs $6.5 $6.2 $3.4 $3.1 $2.9 $2.8 |
Recognized Compensation Expense And Income Tax Benefits | A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three months ended March 31 was as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 Compensation expense $3.2 $5.3 $1.7 $2.8 $1.4 $2.3 Income tax benefits 1.3 2.2 0.7 1.1 0.5 0.9 |
WPL [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Defined Benefit Pension And Other Postretirement Benefits Plans | The components of net periodic benefit costs for sponsored defined benefit pension and OPEB plans for the three months ended March 31 are included in the tables below (in millions). In IPL’s and WPL’s tables below, the defined benefit pension plans amounts represent those respective amounts for their bargaining unit employees covered under the qualified plans that they sponsor, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Alliant Energy and Corporate Services sponsored qualified and non-qualified defined benefit pension plans. In IPL’s and WPL’s tables below, the OPEB plans amounts represent respective amounts for their employees, as well as amounts directly assigned to them related to their current and former non-bargaining employees who are participants in the Corporate Services sponsored OPEB plan. Defined Benefit Pension Plans OPEB Plans Alliant Energy 2017 2016 2017 2016 Service cost $3.1 $3.2 $1.2 $1.3 Interest cost 12.8 13.3 2.2 2.3 Expected return on plan assets (16.4 ) (16.4 ) (1.5 ) (1.5 ) Amortization of prior service credit (0.1 ) (0.1 ) (0.1 ) (1.0 ) Amortization of actuarial loss 9.4 9.3 1.0 1.2 $8.8 $9.3 $2.8 $2.3 Defined Benefit Pension Plans OPEB Plans IPL 2017 2016 2017 2016 Service cost $1.8 $1.9 $0.5 $0.6 Interest cost 5.9 6.1 0.9 1.0 Expected return on plan assets (7.7 ) (7.7 ) (1.1 ) (1.0 ) Amortization of prior service credit — — — (0.7 ) Amortization of actuarial loss 4.0 4.1 0.5 0.6 $4.0 $4.4 $0.8 $0.5 Defined Benefit Pension Plans OPEB Plans WPL 2017 2016 2017 2016 Service cost $1.2 $1.2 $0.5 $0.5 Interest cost 5.5 5.6 0.9 0.9 Expected return on plan assets (7.1 ) (7.1 ) (0.2 ) (0.2 ) Amortization of prior service cost (credit) — 0.1 (0.1 ) (0.2 ) Amortization of actuarial loss 4.6 4.4 0.4 0.5 $4.2 $4.2 $1.5 $1.5 |
Employees Participate In Defined Contribution Retirement Plans | For the three months ended March 31 , costs related to the 401(k) savings plan, which are partially based on the participants’ contributions and include allocated costs associated with Corporate Services employees for IPL and WPL, were as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 401(k) costs $6.5 $6.2 $3.4 $3.1 $2.9 $2.8 |
Recognized Compensation Expense And Income Tax Benefits | A summary of compensation expense, including amounts allocated to IPL and WPL, and the related income tax benefits recognized for share-based compensation awards for the three months ended March 31 was as follows (in millions): Alliant Energy IPL WPL 2017 2016 2017 2016 2017 2016 Compensation expense $3.2 $5.3 $1.7 $2.8 $1.4 $2.3 Income tax benefits 1.3 2.2 0.7 1.1 0.5 0.9 |
Fair Value Measurements (Tables
Fair Value Measurements (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Statement [Line Items] | |
Fair Value Measurements | Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions): Alliant Energy March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $13.3 $— $1.7 $11.6 $13.3 $41.4 $— $4.6 $36.8 $41.4 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 45.3 — 0.8 44.5 45.3 28.6 — 0.5 28.1 28.6 Long-term debt (including current maturities) 4,320.7 — 4,768.3 2.9 4,771.2 4,320.2 — 4,795.7 3.3 4,799.0 Cumulative preferred stock of IPL 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 IPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $8.8 $— $1.3 $7.5 $8.8 $20.8 $— $2.8 $18.0 $20.8 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 16.3 — 0.5 15.8 16.3 8.3 — 0.4 7.9 8.3 Long-term debt 2,154.0 — 2,342.1 — 2,342.1 2,153.5 — 2,352.3 — 2,352.3 Cumulative preferred stock 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 WPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $4.5 $— $0.4 $4.1 $4.5 $20.6 $— $1.8 $18.8 $20.6 Liabilities: Derivatives 29.0 — 0.3 28.7 29.0 20.3 — 0.1 20.2 20.3 Long-term debt 1,535.5 — 1,790.9 — 1,790.9 1,535.2 — 1,807.4 — 1,807.4 |
Fair Value Measurements Using Significant Unobservable Inputs | Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions): Alliant Energy Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $8.7 ($32.7 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (35.2 ) (31.4 ) — — Transfers into Level 3 — 0.9 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (6.3 ) (2.1 ) (62.1 ) (17.8 ) Ending balance, March 31 ($32.9 ) ($65.9 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($33.7 ) ($30.0 ) $— $— IPL Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $10.1 ($1.9 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (12.7 ) (7.6 ) — — Transfers into Level 3 — 0.5 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (5.6 ) (3.5 ) (62.1 ) (17.8 ) Ending balance, March 31 ($8.3 ) ($13.1 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($11.4 ) ($6.6 ) $— $— WPL Commodity Contract Derivative Assets and (Liabilities), net Three Months Ended March 31 2017 2016 Beginning balance, January 1 ($1.4 ) ($30.8 ) Total net losses included in changes in net assets (realized/unrealized) (22.5 ) (23.8 ) Transfers into Level 3 — 0.4 Settlements (0.7 ) 1.4 Ending balance, March 31 ($24.6 ) ($52.8 ) The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($22.3 ) ($23.4 ) (a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold. |
Fair Value Of Net Derivative Assets (Liabilities) | The fair value of electric, natural gas and coal commodity contracts categorized as Level 3 was recognized as net derivative assets (liabilities) as follows (in millions): Alliant Energy IPL WPL Excluding FTRs FTRs Excluding FTRs FTRs Excluding FTRs FTRs March 31, 2017 ($37.0 ) $4.1 ($11.6 ) $3.3 ($25.4 ) $0.8 December 31, 2016 (2.3 ) 11.0 0.1 10.0 (2.4 ) 1.0 |
IPL [Member] | |
Statement [Line Items] | |
Fair Value Measurements | Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions): Alliant Energy March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $13.3 $— $1.7 $11.6 $13.3 $41.4 $— $4.6 $36.8 $41.4 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 45.3 — 0.8 44.5 45.3 28.6 — 0.5 28.1 28.6 Long-term debt (including current maturities) 4,320.7 — 4,768.3 2.9 4,771.2 4,320.2 — 4,795.7 3.3 4,799.0 Cumulative preferred stock of IPL 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 IPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $8.8 $— $1.3 $7.5 $8.8 $20.8 $— $2.8 $18.0 $20.8 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 16.3 — 0.5 15.8 16.3 8.3 — 0.4 7.9 8.3 Long-term debt 2,154.0 — 2,342.1 — 2,342.1 2,153.5 — 2,352.3 — 2,352.3 Cumulative preferred stock 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 WPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $4.5 $— $0.4 $4.1 $4.5 $20.6 $— $1.8 $18.8 $20.6 Liabilities: Derivatives 29.0 — 0.3 28.7 29.0 20.3 — 0.1 20.2 20.3 Long-term debt 1,535.5 — 1,790.9 — 1,790.9 1,535.2 — 1,807.4 — 1,807.4 |
Fair Value Measurements Using Significant Unobservable Inputs | Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions): Alliant Energy Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $8.7 ($32.7 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (35.2 ) (31.4 ) — — Transfers into Level 3 — 0.9 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (6.3 ) (2.1 ) (62.1 ) (17.8 ) Ending balance, March 31 ($32.9 ) ($65.9 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($33.7 ) ($30.0 ) $— $— IPL Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $10.1 ($1.9 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (12.7 ) (7.6 ) — — Transfers into Level 3 — 0.5 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (5.6 ) (3.5 ) (62.1 ) (17.8 ) Ending balance, March 31 ($8.3 ) ($13.1 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($11.4 ) ($6.6 ) $— $— WPL Commodity Contract Derivative Assets and (Liabilities), net Three Months Ended March 31 2017 2016 Beginning balance, January 1 ($1.4 ) ($30.8 ) Total net losses included in changes in net assets (realized/unrealized) (22.5 ) (23.8 ) Transfers into Level 3 — 0.4 Settlements (0.7 ) 1.4 Ending balance, March 31 ($24.6 ) ($52.8 ) The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($22.3 ) ($23.4 ) (a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold. |
Fair Value Of Net Derivative Assets (Liabilities) | The fair value of electric, natural gas and coal commodity contracts categorized as Level 3 was recognized as net derivative assets (liabilities) as follows (in millions): Alliant Energy IPL WPL Excluding FTRs FTRs Excluding FTRs FTRs Excluding FTRs FTRs March 31, 2017 ($37.0 ) $4.1 ($11.6 ) $3.3 ($25.4 ) $0.8 December 31, 2016 (2.3 ) 11.0 0.1 10.0 (2.4 ) 1.0 |
WPL [Member] | |
Statement [Line Items] | |
Fair Value Measurements | Carrying amounts and related estimated fair values of other financial instruments were as follows (in millions): Alliant Energy March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $13.3 $— $1.7 $11.6 $13.3 $41.4 $— $4.6 $36.8 $41.4 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 45.3 — 0.8 44.5 45.3 28.6 — 0.5 28.1 28.6 Long-term debt (including current maturities) 4,320.7 — 4,768.3 2.9 4,771.2 4,320.2 — 4,795.7 3.3 4,799.0 Cumulative preferred stock of IPL 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 IPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $8.8 $— $1.3 $7.5 $8.8 $20.8 $— $2.8 $18.0 $20.8 Deferred proceeds 149.0 — — 149.0 149.0 211.1 — — 211.1 211.1 Liabilities and equity: Derivatives 16.3 — 0.5 15.8 16.3 8.3 — 0.4 7.9 8.3 Long-term debt 2,154.0 — 2,342.1 — 2,342.1 2,153.5 — 2,352.3 — 2,352.3 Cumulative preferred stock 200.0 202.6 — — 202.6 200.0 194.8 — — 194.8 WPL March 31, 2017 December 31, 2016 Fair Value Fair Value Carrying Level Level Level Carrying Level Level Level Amount 1 2 3 Total Amount 1 2 3 Total Assets: Derivatives $4.5 $— $0.4 $4.1 $4.5 $20.6 $— $1.8 $18.8 $20.6 Liabilities: Derivatives 29.0 — 0.3 28.7 29.0 20.3 — 0.1 20.2 20.3 Long-term debt 1,535.5 — 1,790.9 — 1,790.9 1,535.2 — 1,807.4 — 1,807.4 |
Fair Value Measurements Using Significant Unobservable Inputs | Information for fair value measurements using significant unobservable inputs (Level 3 inputs) was as follows (in millions): Alliant Energy Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $8.7 ($32.7 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (35.2 ) (31.4 ) — — Transfers into Level 3 — 0.9 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (6.3 ) (2.1 ) (62.1 ) (17.8 ) Ending balance, March 31 ($32.9 ) ($65.9 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($33.7 ) ($30.0 ) $— $— IPL Commodity Contract Derivative Assets and (Liabilities), net Deferred Proceeds Three Months Ended March 31 2017 2016 2017 2016 Beginning balance, January 1 $10.1 ($1.9 ) $211.1 $172.0 Total net losses included in changes in net assets (realized/unrealized) (12.7 ) (7.6 ) — — Transfers into Level 3 — 0.5 — — Sales (0.1 ) (0.6 ) — — Settlements (a) (5.6 ) (3.5 ) (62.1 ) (17.8 ) Ending balance, March 31 ($8.3 ) ($13.1 ) $149.0 $154.2 The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($11.4 ) ($6.6 ) $— $— WPL Commodity Contract Derivative Assets and (Liabilities), net Three Months Ended March 31 2017 2016 Beginning balance, January 1 ($1.4 ) ($30.8 ) Total net losses included in changes in net assets (realized/unrealized) (22.5 ) (23.8 ) Transfers into Level 3 — 0.4 Settlements (0.7 ) 1.4 Ending balance, March 31 ($24.6 ) ($52.8 ) The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 ($22.3 ) ($23.4 ) (a) Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold. |
Fair Value Of Net Derivative Assets (Liabilities) | The fair value of electric, natural gas and coal commodity contracts categorized as Level 3 was recognized as net derivative assets (liabilities) as follows (in millions): Alliant Energy IPL WPL Excluding FTRs FTRs Excluding FTRs FTRs Excluding FTRs FTRs March 31, 2017 ($37.0 ) $4.1 ($11.6 ) $3.3 ($25.4 ) $0.8 December 31, 2016 (2.3 ) 11.0 0.1 10.0 (2.4 ) 1.0 |
Derivative Instruments (Tables)
Derivative Instruments (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Derivative Instruments [Line Items] | |
Notional Amounts Of Derivative Instruments | As of March 31, 2017 , gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands): Electricity FTRs Natural Gas Coal Diesel Fuel MWhs Years MWhs Years Dths Years Tons Years Gallons Years Alliant Energy 2,304 2017-2018 3,537 2017 160,048 2017-2026 4,113 2017-2019 5,796 2017-2018 IPL — — 2,229 2017 72,924 2017-2026 1,680 2017-2019 — — WPL 2,304 2017-2018 1,308 2017 87,124 2017-2026 2,433 2017-2018 5,796 2017-2018 |
Fair Value Of Financial Instruments | The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other liabilities” on the balance sheets as follows (in millions): Alliant Energy IPL WPL Commodity contracts March 31, December 31, March 31, December 31, March 31, December 31, Current derivative assets $12.2 $29.4 $8.2 $19.1 $4.0 $10.3 Non-current derivative assets 1.1 12.0 0.6 1.7 0.5 10.3 Current derivative liabilities 13.4 13.3 2.9 2.7 10.5 10.6 Non-current derivative liabilities 31.9 15.3 13.4 5.6 18.5 9.7 |
IPL [Member] | |
Derivative Instruments [Line Items] | |
Notional Amounts Of Derivative Instruments | As of March 31, 2017 , gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands): Electricity FTRs Natural Gas Coal Diesel Fuel MWhs Years MWhs Years Dths Years Tons Years Gallons Years Alliant Energy 2,304 2017-2018 3,537 2017 160,048 2017-2026 4,113 2017-2019 5,796 2017-2018 IPL — — 2,229 2017 72,924 2017-2026 1,680 2017-2019 — — WPL 2,304 2017-2018 1,308 2017 87,124 2017-2026 2,433 2017-2018 5,796 2017-2018 |
Fair Value Of Financial Instruments | The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other liabilities” on the balance sheets as follows (in millions): Alliant Energy IPL WPL Commodity contracts March 31, December 31, March 31, December 31, March 31, December 31, Current derivative assets $12.2 $29.4 $8.2 $19.1 $4.0 $10.3 Non-current derivative assets 1.1 12.0 0.6 1.7 0.5 10.3 Current derivative liabilities 13.4 13.3 2.9 2.7 10.5 10.6 Non-current derivative liabilities 31.9 15.3 13.4 5.6 18.5 9.7 |
WPL [Member] | |
Derivative Instruments [Line Items] | |
Notional Amounts Of Derivative Instruments | As of March 31, 2017 , gross notional amounts and settlement/delivery years related to outstanding swap contracts, option contracts, physical forward contracts, FTRs, coal contracts and diesel fuel contracts that were accounted for as commodity derivative instruments were as follows (units in thousands): Electricity FTRs Natural Gas Coal Diesel Fuel MWhs Years MWhs Years Dths Years Tons Years Gallons Years Alliant Energy 2,304 2017-2018 3,537 2017 160,048 2017-2026 4,113 2017-2019 5,796 2017-2018 IPL — — 2,229 2017 72,924 2017-2026 1,680 2017-2019 — — WPL 2,304 2017-2018 1,308 2017 87,124 2017-2026 2,433 2017-2018 5,796 2017-2018 |
Fair Value Of Financial Instruments | The fair values of current derivative assets are included in “Other current assets,” non-current derivative assets are included in “Deferred charges and other,” current derivative liabilities are included in “Other current liabilities” and non-current derivative liabilities are included in “Other liabilities” on the balance sheets as follows (in millions): Alliant Energy IPL WPL Commodity contracts March 31, December 31, March 31, December 31, March 31, December 31, Current derivative assets $12.2 $29.4 $8.2 $19.1 $4.0 $10.3 Non-current derivative assets 1.1 12.0 0.6 1.7 0.5 10.3 Current derivative liabilities 13.4 13.3 2.9 2.7 10.5 10.6 Non-current derivative liabilities 31.9 15.3 13.4 5.6 18.5 9.7 |
Commitments And Contingencies (
Commitments And Contingencies (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Commitments and Contingencies [Line Items] | |
Operating Expense Purchase Obligations | At March 31, 2017 , minimum future commitments related to these operating expense purchase obligations were as follows (in millions): Alliant Energy IPL WPL Purchased power (a) $1,372 $1,266 $106 Natural gas 812 426 386 Coal (b) 165 73 92 Other (c) 38 20 3 $2,387 $1,785 $587 (a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased. (b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of March 31, 2017 regarding expected future usage, which is subject to change. (c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2017 . |
MGP Site Estimated Future Costs And Recorded Liabilities | At March 31, 2017 , estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions). At March 31, 2017 , such amounts for WPL were not material. Alliant Energy IPL Range of estimated future costs $12 - $31 $10 - $28 Current and non-current environmental liabilities 17 14 |
IPL [Member] | |
Commitments and Contingencies [Line Items] | |
Operating Expense Purchase Obligations | At March 31, 2017 , minimum future commitments related to these operating expense purchase obligations were as follows (in millions): Alliant Energy IPL WPL Purchased power (a) $1,372 $1,266 $106 Natural gas 812 426 386 Coal (b) 165 73 92 Other (c) 38 20 3 $2,387 $1,785 $587 (a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased. (b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of March 31, 2017 regarding expected future usage, which is subject to change. (c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2017 . |
MGP Site Estimated Future Costs And Recorded Liabilities | At March 31, 2017 , estimated future costs expected to be incurred for the investigation, remediation and monitoring of the MGP sites, as well as environmental liabilities recorded on the balance sheets for these sites, were as follows (in millions). At March 31, 2017 , such amounts for WPL were not material. Alliant Energy IPL Range of estimated future costs $12 - $31 $10 - $28 Current and non-current environmental liabilities 17 14 |
WPL [Member] | |
Commitments and Contingencies [Line Items] | |
Operating Expense Purchase Obligations | At March 31, 2017 , minimum future commitments related to these operating expense purchase obligations were as follows (in millions): Alliant Energy IPL WPL Purchased power (a) $1,372 $1,266 $106 Natural gas 812 426 386 Coal (b) 165 73 92 Other (c) 38 20 3 $2,387 $1,785 $587 (a) Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased. (b) Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of March 31, 2017 regarding expected future usage, which is subject to change. (c) Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2017 . |
Segments Of Business (Tables)
Segments Of Business (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Segment Reporting Information [Line Items] | |
Schedule Of Segments Of Business | Certain financial information relating to Alliant Energy’s business segments is as follows. Intersegment revenues were not material to Alliant Energy’s operations. Utility (a) Non-Regulated, Alliant Energy Electric Gas Other Total Parent and Other Consolidated (in millions) Three Months Ended March 31, 2017 Operating revenues $677.6 $154.3 $11.7 $843.6 $10.3 $853.9 Operating income 107.2 28.0 0.4 135.6 7.3 142.9 Amounts attributable to Alliant Energy common shareowners: Income from continuing operations, net of tax 89.6 9.4 99.0 Income from discontinued operations, net of tax — 1.4 1.4 Net income 89.6 10.8 100.4 Three Months Ended March 31, 2016 Operating revenues $668.9 $152.2 $13.2 $834.3 $9.5 $843.8 Operating income 109.8 28.8 2.2 140.8 5.1 145.9 Amounts attributable to Alliant Energy common shareowners: Income from continuing operations, net of tax 92.1 5.5 97.6 Loss from discontinued operations, net of tax — (1.1 ) (1.1 ) Net income 92.1 4.4 96.5 (a) Alliant Energy’s utility business segments include: a) utility electric operations, which include Alliant Energy’s entire investment in ATC; b) utility gas operations; and c) utility other, which includes steam operations and the unallocated portions of the utility business. |
IPL [Member] | |
Segment Reporting Information [Line Items] | |
Schedule Of Segments Of Business | Certain financial information relating to IPL’s business segments is as follows. Intersegment revenues were not material to IPL’s operations. Electric Gas Other Total (in millions) Three Months Ended March 31, 2017 Operating revenues $356.2 $83.1 $11.2 $450.5 Operating income 33.8 14.4 1.4 49.6 Earnings available for common stock 37.2 Three Months Ended March 31, 2016 Operating revenues $361.6 $84.2 $12.9 $458.7 Operating income 43.4 15.8 2.8 62.0 Earnings available for common stock 45.6 |
WPL [Member] | |
Segment Reporting Information [Line Items] | |
Schedule Of Segments Of Business | Certain financial information relating to WPL’s business segments is as follows. Intersegment revenues were not material to WPL’s operations. Electric Gas Other Total (in millions) Three Months Ended March 31, 2017 Operating revenues $321.4 $71.2 $0.5 $393.1 Operating income (loss) 73.4 13.6 (1.0 ) 86.0 Earnings available for common stock 45.5 Three Months Ended March 31, 2016 Operating revenues $307.3 $68.0 $0.3 $375.6 Operating income (loss) 66.4 13.0 (0.6 ) 78.8 Earnings available for common stock 46.5 |
Related Parties (Tables)
Related Parties (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Related Party Transactions [Line Items] | |
Services Provided, Sales Credited And Purchases | The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions): IPL WPL 2017 2016 2017 2016 Corporate Services billings $39 $38 $31 $33 Sales credited 2 1 — 1 Purchases billed 66 96 34 19 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions): IPL WPL March 31, 2017 December 31, 2016 March 31, 2017 December 31, 2016 Net payables to Corporate Services $103 $104 $65 $72 |
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions): 2017 2016 ATC, LLC billings to WPL $26 $27 WPL billings to ATC, LLC 3 3 |
IPL [Member] | |
Related Party Transactions [Line Items] | |
Services Provided, Sales Credited And Purchases | The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions): IPL WPL 2017 2016 2017 2016 Corporate Services billings $39 $38 $31 $33 Sales credited 2 1 — 1 Purchases billed 66 96 34 19 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions): IPL WPL March 31, 2017 December 31, 2016 March 31, 2017 December 31, 2016 Net payables to Corporate Services $103 $104 $65 $72 |
WPL [Member] | |
Related Party Transactions [Line Items] | |
Services Provided, Sales Credited And Purchases | The amounts billed for services provided, sales credited and purchases for the three months ended March 31 were as follows (in millions): IPL WPL 2017 2016 2017 2016 Corporate Services billings $39 $38 $31 $33 Sales credited 2 1 — 1 Purchases billed 66 96 34 19 |
Net Intercompany Payables | Net intercompany payables to Corporate Services were as follows (in millions): IPL WPL March 31, 2017 December 31, 2016 March 31, 2017 December 31, 2016 Net payables to Corporate Services $103 $104 $65 $72 |
Related Amounts Billed Between Parties | The related amounts billed between the parties for the three months ended March 31 were as follows (in millions): 2017 2016 ATC, LLC billings to WPL $26 $27 WPL billings to ATC, LLC 3 3 |
Discontinued Operations (Tables
Discontinued Operations (Tables) | 3 Months Ended |
Mar. 31, 2017 | |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] | |
Discontinued Operations in Income Statement | A summary of the components of discontinued operations in Alliant Energy’s income statements for the three months ended March 31 was as follows (in millions): 2017 2016 Operating expenses (income) ($2.3 ) $1.9 Income (loss) before income taxes 2.3 (1.9 ) Income tax expense (benefit) 0.9 (0.8 ) Income (loss) from discontinued operations, net of tax $1.4 ($1.1 ) |
Summary Of Significant Accoun35
Summary Of Significant Accounting Policies (Narrative) (Details) | 1 Months Ended |
May 31, 2016 | |
Summary of Significant Accounting Policies [Line Items] | |
Common stock split conversion ratio (2:1) | 2 |
Regulatory Matters (Narrative)
Regulatory Matters (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended | ||
Mar. 31, 2017 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | |
Regulatory Matters [Line Items] | ||||
Regulatory assets | $ 1,963 | $ 1,915.1 | ||
Regulatory liabilities | 696.6 | 681 | ||
IPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Regulatory assets | 1,500.8 | 1,458.8 | ||
Regulatory liabilities | 448.3 | 430.8 | ||
WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Regulatory assets | 462.2 | 456.3 | ||
Regulatory liabilities | 248.3 | 250.2 | ||
2017 and 2018 Test Period Retail Electric [Member] | Alliant Energy and WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Increase in electric revenues | 22 | |||
2017 and 2018 Test Period Retail Gas [Member] | Alliant Energy and WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Increase in gas revenues | $ 2 | |||
2017 Test Year Retail Electric Fuel Related [Member] | WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Annual bandwidth for fuel-related costs | 2.00% | |||
2016 Test Year Retail Electric Fuel-Related [Member] | WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Annual bandwidth for fuel-related costs | 2.00% | |||
Scenario, Forecast [Member] | 2016 Test Year Retail Electric [Member] | IPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Requested rate increase (decrease), amount | $ 176 | |||
Requested rate increase (decrease), percent | 12.00% | |||
Interim rate increase (decrease), amount | $ 102 | |||
Interim rate increase (decrease), percent | 7.00% | |||
Scenario, Forecast [Member] | 2017 and 2018 Test Period Retail Electric [Member] | WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Authorized increase (decrease) in final rates, amount | $ 9 | |||
Authorized increase (decrease) in final rates, percent | 1.00% | |||
Increase in base rates | $ 60 | |||
Reduction in fuel-related costs | 51 | |||
Scenario, Forecast [Member] | 2017 and 2018 Test Period Retail Gas [Member] | WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Authorized increase (decrease) in final rates, amount | $ 9 | |||
Authorized increase (decrease) in final rates, percent | 13.00% | |||
Scenario, Forecast [Member] | 2017 Test Year Retail Electric Fuel Related [Member] | WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Under-collection of retail fuel-related costs | $ 8 | |||
FERC [Member] | MISO Transmission Owner Complaints [Member] | ||||
Regulatory Matters [Line Items] | ||||
Base return on equity for refund period from November 12, 2013 through February 11, 2015, percent | 10.32% | |||
Refund received subject to final true-up | $ 51 | |||
FERC [Member] | MISO Transmission Owner Complaints [Member] | IPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Refund received subject to final true-up | 40 | |||
FERC [Member] | MISO Transmission Owner Complaints [Member] | WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Refund received subject to final true-up | 11 | |||
Commodity cost recovery [Member] | 2017 Test Year Retail Electric Fuel Related [Member] | Alliant Energy and WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Regulatory assets | 1 | |||
Commodity cost recovery [Member] | ||||
Regulatory Matters [Line Items] | ||||
Regulatory liabilities | 32.9 | 30.8 | ||
Commodity cost recovery [Member] | IPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Regulatory liabilities | 20.1 | 17.8 | ||
Commodity cost recovery [Member] | WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Regulatory liabilities | 12.8 | $ 13 | ||
Commodity cost recovery [Member] | 2016 Test Year Retail Electric Fuel-Related [Member] | Alliant Energy and WPL [Member] | ||||
Regulatory Matters [Line Items] | ||||
Regulatory liabilities | $ 9 |
Regulatory Matters (Regulatory
Regulatory Matters (Regulatory Assets) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
Regulatory Assets [Line Items] | ||
Regulatory assets | $ 1,963 | $ 1,915.1 |
Tax-related [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 1,080.2 | 1,055.6 |
Pension and OPEB costs [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 568.5 | 578.7 |
Asset retirement obligations [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 108.6 | 105.9 |
Derivatives [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 46.4 | 30.7 |
WPL's EGUs retired early [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 39.7 | 41.4 |
Emission allowances [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 26 | 26.2 |
Other [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 93.6 | 76.6 |
IPL [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 1,500.8 | 1,458.8 |
IPL [Member] | Tax-related [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 1,044.9 | 1,022.4 |
IPL [Member] | Pension and OPEB costs [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 289.1 | 294 |
IPL [Member] | Asset retirement obligations [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 67.1 | 64.3 |
IPL [Member] | Derivatives [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 17.2 | 10 |
IPL [Member] | Emission allowances [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 26 | 26.2 |
IPL [Member] | Other [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 56.5 | 41.9 |
WPL [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 462.2 | 456.3 |
WPL [Member] | Tax-related [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 35.3 | 33.2 |
WPL [Member] | Pension and OPEB costs [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 279.4 | 284.7 |
WPL [Member] | Asset retirement obligations [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 41.5 | 41.6 |
WPL [Member] | Derivatives [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 29.2 | 20.7 |
WPL [Member] | WPL's EGUs retired early [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | 39.7 | 41.4 |
WPL [Member] | Other [Member] | ||
Regulatory Assets [Line Items] | ||
Regulatory assets | $ 37.1 | $ 34.7 |
Regulatory Matters (Regulator38
Regulatory Matters (Regulatory Liabilities) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | $ 696.6 | $ 681 |
Cost of removal obligations [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 413 | 411.6 |
Electric transmission cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 128.3 | 72 |
IPL's tax benefit riders [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 64.7 | 83.5 |
Commodity cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 32.9 | 30.8 |
Energy efficiency cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 20.6 | 20.5 |
Derivatives [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 9 | 31.5 |
Other [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 28.1 | 31.1 |
IPL [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 448.3 | 430.8 |
IPL [Member] | Cost of removal obligations [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 271.1 | 269.4 |
IPL [Member] | Electric transmission cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 75.9 | 35.7 |
IPL [Member] | IPL's tax benefit riders [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 64.7 | 83.5 |
IPL [Member] | Commodity cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 20.1 | 17.8 |
IPL [Member] | Energy efficiency cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 0 | 0 |
IPL [Member] | Derivatives [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 5.1 | 12.1 |
IPL [Member] | Other [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 11.4 | 12.3 |
WPL [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 248.3 | 250.2 |
WPL [Member] | Cost of removal obligations [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 141.9 | 142.2 |
WPL [Member] | Electric transmission cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 52.4 | 36.3 |
WPL [Member] | Commodity cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 12.8 | 13 |
WPL [Member] | Energy efficiency cost recovery [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 20.6 | 20.5 |
WPL [Member] | Derivatives [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | 3.9 | 19.4 |
WPL [Member] | Other [Member] | ||
Regulatory Liabilities [Line Items] | ||
Regulatory liabilities | $ 16.7 | $ 18.8 |
Regulatory Matters (Tax Benefit
Regulatory Matters (Tax Benefit Riders) (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Regulatory Liabilities [Line Items] | ||
Increase (decrease) in regulatory liabilities | $ 14.2 | $ (28.7) |
Alliant Energy and IPL [Member] | Electric tax benefit rider [Member] | ||
Regulatory Liabilities [Line Items] | ||
Increase (decrease) in regulatory liabilities | (17) | |
Alliant Energy and IPL [Member] | Gas tax benefit rider [Member] | ||
Regulatory Liabilities [Line Items] | ||
Increase (decrease) in regulatory liabilities | (2) | |
Alliant Energy and IPL [Member] | Tax benefit riders [Member] | ||
Regulatory Liabilities [Line Items] | ||
Increase (decrease) in regulatory liabilities | $ (19) |
Property, Plant and Equipment (
Property, Plant and Equipment (Narrative) (Details) $ in Millions | 3 Months Ended | ||
Mar. 31, 2017USD ($)MW | Mar. 31, 2016USD ($) | Apr. 30, 2017USD ($) | |
Property, Plant and Equipment [Line Items] | |||
Allowance for funds used during construction | $ 17 | $ 13.2 | |
IPL [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Allowance for funds used during construction | 14.3 | 10.3 | |
WPL [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Allowance for funds used during construction | $ 2.7 | $ 2.9 | |
Marshalltown [Member] | IPL [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Fossil-fueled EGU capacity (in megawatts) | MW | 660 | ||
Marshalltown [Member] | Alliant Energy and IPL [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Capitalized expenditures | $ 635 | ||
Allowance for funds used during construction | $ 79 | ||
Riverside Energy Center Expansion [Member] | WPL [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Fossil-fueled EGU capacity (in megawatts) | MW | 730 | ||
Riverside Energy Center Expansion [Member] | Alliant Energy and WPL [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Allowance for funds used during construction | $ 3 | ||
Construction work in progress | $ 129 | ||
Subsequent Event [Member] | Franklin County Wind Farm [Member] | |||
Property, Plant and Equipment [Line Items] | |||
Value of Franklin County wind farm | $ 33 |
Receivables (Narrative) (Detail
Receivables (Narrative) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 | |
Receivables [Line Items] | |||
Deferred proceeds | $ 149 | $ 211.1 | |
IPL [Member] | |||
Receivables [Line Items] | |||
Deferred proceeds | 149 | 211.1 | |
Receivables Sold [Member] | IPL [Member] | |||
Receivables [Line Items] | |||
Receivables sold to third party | 221 | 248.1 | |
Cash proceeds of receivables sold | [1] | 56 | 21 |
Deferred proceeds | 149 | $ 211.1 | |
Available capacity | 41.8 | ||
Outstanding receivables past due | $ 69.9 | ||
[1] | Changes in cash proceeds are presented in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s cash flows statements. |
Receivables (Maximum And Averag
Receivables (Maximum And Average Outstanding Cash Proceeds) (Details) - IPL [Member] - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Receivables [Line Items] | ||
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 38.4 | $ 39.1 |
Maximum [Member] | ||
Receivables [Line Items] | ||
Outstanding aggregate cash proceeds (based on daily outstanding balances) | $ 79 | $ 75 |
Receivables (Receivables Sold U
Receivables (Receivables Sold Under The Agreement) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 | |
Receivables [Line Items] | |||
Fair value of deferred proceeds | $ 149 | $ 211.1 | |
IPL [Member] | |||
Receivables [Line Items] | |||
Fair value of deferred proceeds | 149 | 211.1 | |
Receivables Sold [Member] | IPL [Member] | |||
Receivables [Line Items] | |||
Customer accounts receivable | 143.7 | 157.6 | |
Unbilled utility revenues | 76.8 | 90.4 | |
Other receivables | 0.5 | 0.1 | |
Receivables sold to third party | 221 | 248.1 | |
Less: cash proceeds | [1] | 56 | 21 |
Deferred proceeds | 165 | 227.1 | |
Less: allowance for doubtful accounts | 16 | 16 | |
Fair value of deferred proceeds | $ 149 | $ 211.1 | |
[1] | Changes in cash proceeds are presented in “Sales of accounts receivable” in operating activities in Alliant Energy’s and IPL’s cash flows statements. |
Receivables (Additional Attribu
Receivables (Additional Attributes Of Receivables Sold Under The Agreement) (Details) - IPL [Member] - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Receivables [Line Items] | ||
Collections reinvested in receivables | $ 501.2 | $ 440.2 |
Write-offs, net of recoveries | $ 4.6 | $ 0.4 |
Investments (Narrative) (Detail
Investments (Narrative) (Details) $ in Millions | 3 Months Ended |
Mar. 31, 2016USD ($) | |
Schedule of Investments [Line Items] | |
Proceeds from liquidation of company-owned life insurance policies | $ 26 |
IPL [Member] | |
Schedule of Investments [Line Items] | |
Proceeds from liquidation of company-owned life insurance policies | $ 18 |
Investments (Unconsolidated Equ
Investments (Unconsolidated Equity Investments) (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Schedule of Investments [Line Items] | ||
Equity (income) loss from unconsolidated investments, net | $ (11.5) | $ (10.5) |
WPL [Member] | ||
Schedule of Investments [Line Items] | ||
Equity (income) loss from unconsolidated investments, net | 0 | (10.7) |
ATC Investment [Member] | ||
Schedule of Investments [Line Items] | ||
Equity (income) loss from unconsolidated investments, net | (11.5) | (10.7) |
ATC Investment [Member] | WPL [Member] | ||
Schedule of Investments [Line Items] | ||
Equity (income) loss from unconsolidated investments, net | 0 | (10.7) |
Other [Member] | ||
Schedule of Investments [Line Items] | ||
Equity (income) loss from unconsolidated investments, net | 0 | 0.2 |
Other [Member] | WPL [Member] | ||
Schedule of Investments [Line Items] | ||
Equity (income) loss from unconsolidated investments, net | $ 0 | $ 0 |
Common Equity (Narrative) (Deta
Common Equity (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Common Equity [Line Items] | ||
Comprehensive income | $ 0 | $ 0 |
IPL [Member] | ||
Common Equity [Line Items] | ||
Retained earnings free of dividend restrictions | 616 | |
Restricted net assets of subsidiaries | 1,600 | |
Comprehensive income | 0 | 0 |
WPL [Member] | ||
Common Equity [Line Items] | ||
Retained earnings free of dividend restrictions | 95 | |
Restricted net assets of subsidiaries | 1,700 | |
Comprehensive income | $ 0 | $ 0 |
Common Equity (Common Share Act
Common Equity (Common Share Activity) (Details) | 3 Months Ended |
Mar. 31, 2017shares | |
Common Stock Oustanding [Roll Forward] | |
Shares outstanding, January 1, 2017 (in shares) | 227,673,654 |
Shareowner Direct Plan issuances (in shares) | 190,286 |
Equity-based compensation plans (in shares) | 5,185 |
Other (in shares) | (45,847) |
Shares outstanding, March 31, 2017 (in shares) | 227,823,278 |
Debt (Credit Facilities) (Detai
Debt (Credit Facilities) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
Debt [Line Items] | ||
Commercial paper outstanding | $ 302.8 | $ 244.1 |
Commercial paper weighted average interest rates | 1.10% | |
Available credit facility capacity | $ 697.2 | |
Parent Company [Member] | ||
Debt [Line Items] | ||
Commercial paper outstanding | $ 202.4 | |
Commercial paper weighted average interest rates | 1.20% | |
Available credit facility capacity | $ 97.6 | |
IPL [Member] | ||
Debt [Line Items] | ||
Commercial paper outstanding | $ 9.2 | 0 |
Commercial paper weighted average interest rates | 1.20% | |
Available credit facility capacity | $ 290.8 | |
WPL [Member] | ||
Debt [Line Items] | ||
Commercial paper outstanding | $ 91.2 | $ 52.3 |
Commercial paper weighted average interest rates | 0.90% | |
Available credit facility capacity | $ 308.8 |
Debt (Other Short-Term Borrowin
Debt (Other Short-Term Borrowings) (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Debt [Line Items] | ||
Maximum amount outstanding (based on daily outstanding balances) | $ 325.5 | $ 242.6 |
Average amount outstanding (based on daily outstanding balances) | $ 276.5 | $ 199 |
Weighted average interest rates | 0.90% | 0.60% |
IPL [Member] | ||
Debt [Line Items] | ||
Maximum amount outstanding (based on daily outstanding balances) | $ 9.2 | $ 0 |
Average amount outstanding (based on daily outstanding balances) | $ 0.1 | 0 |
Weighted average interest rates | 1.10% | |
WPL [Member] | ||
Debt [Line Items] | ||
Maximum amount outstanding (based on daily outstanding balances) | $ 113.6 | 55.7 |
Average amount outstanding (based on daily outstanding balances) | $ 79.1 | $ 25.8 |
Weighted average interest rates | 0.70% | 0.40% |
Income Taxes (Narrative) (Detai
Income Taxes (Narrative) (Details) $ in Millions | 3 Months Ended |
Mar. 31, 2017USD ($) | |
Income Taxes [Line Items] | |
Increase in deferred tax liabilities | $ 55.7 |
IPL [Member] | |
Income Taxes [Line Items] | |
Increase in deferred tax liabilities | 41.4 |
WPL [Member] | |
Income Taxes [Line Items] | |
Increase in deferred tax liabilities | $ 13.1 |
Income Taxes (Schedule Of Effec
Income Taxes (Schedule Of Effective Income Tax Rates) (Details) | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Effective Tax Rate [Line Items] | ||
Statutory federal income tax rate | 35.00% | 35.00% |
IPL's tax benefit riders | (7.80%) | (8.70%) |
Effect of rate-making on property-related differences | (7.50%) | (6.80%) |
Production tax credits | (5.90%) | (6.30%) |
Other items, net | 1.00% | 4.50% |
Overall income tax rate | 14.80% | 17.70% |
IPL [Member] | ||
Effective Tax Rate [Line Items] | ||
Statutory federal income tax rate | 35.00% | 35.00% |
IPL's tax benefit riders | (19.40%) | (20.70%) |
Effect of rate-making on property-related differences | (17.90%) | (15.20%) |
Production tax credits | (6.60%) | (6.70%) |
Other items, net | (1.30%) | 5.90% |
Overall income tax rate | (10.20%) | (1.70%) |
WPL [Member] | ||
Effective Tax Rate [Line Items] | ||
Statutory federal income tax rate | 35.00% | 35.00% |
Effect of rate-making on property-related differences | (1.70%) | (0.80%) |
Production tax credits | (7.00%) | (6.50%) |
Other items, net | 4.70% | 4.80% |
Overall income tax rate | 31.00% | 32.50% |
Income Taxes (Summary Of Tax Cr
Income Taxes (Summary Of Tax Credit Carryforwards) (Details) $ in Millions | Mar. 31, 2017USD ($) |
Federal [Member] | |
Carryforwards [Line Items] | |
Net operating losses, carryforward amount | $ 633 |
Tax credits, carryforward amount | 284 |
Federal [Member] | IPL [Member] | |
Carryforwards [Line Items] | |
Net operating losses, carryforward amount | 315 |
Tax credits, carryforward amount | 104 |
Federal [Member] | WPL [Member] | |
Carryforwards [Line Items] | |
Net operating losses, carryforward amount | 217 |
Tax credits, carryforward amount | 118 |
State [Member] | |
Carryforwards [Line Items] | |
Net operating losses, carryforward amount | 696 |
State [Member] | IPL [Member] | |
Carryforwards [Line Items] | |
Net operating losses, carryforward amount | 13 |
State [Member] | WPL [Member] | |
Carryforwards [Line Items] | |
Net operating losses, carryforward amount | $ 2 |
Benefit Plans (Narrative) (Deta
Benefit Plans (Narrative) (Details) $ / shares in Units, $ in Millions | 3 Months Ended |
Mar. 31, 2017USD ($)$ / sharesshares | |
Defined Benefit Plan Disclosure [Line Items] | |
Unrecognized compensation cost | $ | $ 14 |
Minimum [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Unrecognized compensation cost recognized over a weighted average period | 1 year |
Maximum [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Unrecognized compensation cost recognized over a weighted average period | 2 years |
IPL [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Unrecognized compensation cost | $ | $ 7.6 |
WPL [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Unrecognized compensation cost | $ | $ 5.9 |
Performance Contingent Restricted Stock [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Nonvested, March 31 (in shares/awards) | shares | 90,806 |
Nonvested, March 31, weighted average grant date fair value (in dollars per share) | $ / shares | $ 32.55 |
Performance Contingent Cash Awards [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Nonvested, March 31 (in shares/awards) | shares | 79,616 |
2014 Grant [Member] | Performance Contingent Restricted Stock [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Vested (in shares/awards) | shares | (99,438) |
2014 Grant [Member] | Performance Contingent Cash Awards [Member] | |
Defined Benefit Plan Disclosure [Line Items] | |
Vested (in shares/awards) | shares | (79,719) |
Cash payout value | $ | $ 3.1 |
Benefit Plans (Defined Benefit
Benefit Plans (Defined Benefit Pension And Other Postretirement Benefits Plans) (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Defined benefit pension plans [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Service cost | $ 3.1 | $ 3.2 |
Interest cost | 12.8 | 13.3 |
Expected return on plan assets | (16.4) | (16.4) |
Amortization of prior service cost (credit) | (0.1) | (0.1) |
Amortization of actuarial loss | 9.4 | 9.3 |
Total | 8.8 | 9.3 |
OPEB Plans [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Service cost | 1.2 | 1.3 |
Interest cost | 2.2 | 2.3 |
Expected return on plan assets | (1.5) | (1.5) |
Amortization of prior service cost (credit) | (0.1) | (1) |
Amortization of actuarial loss | 1 | 1.2 |
Total | 2.8 | 2.3 |
IPL [Member] | Defined benefit pension plans [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Service cost | 1.8 | 1.9 |
Interest cost | 5.9 | 6.1 |
Expected return on plan assets | (7.7) | (7.7) |
Amortization of prior service cost (credit) | 0 | 0 |
Amortization of actuarial loss | 4 | 4.1 |
Total | 4 | 4.4 |
IPL [Member] | OPEB Plans [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Service cost | 0.5 | 0.6 |
Interest cost | 0.9 | 1 |
Expected return on plan assets | (1.1) | (1) |
Amortization of prior service cost (credit) | 0 | (0.7) |
Amortization of actuarial loss | 0.5 | 0.6 |
Total | 0.8 | 0.5 |
WPL [Member] | Defined benefit pension plans [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Service cost | 1.2 | 1.2 |
Interest cost | 5.5 | 5.6 |
Expected return on plan assets | (7.1) | (7.1) |
Amortization of prior service cost (credit) | 0 | 0.1 |
Amortization of actuarial loss | 4.6 | 4.4 |
Total | 4.2 | 4.2 |
WPL [Member] | OPEB Plans [Member] | ||
Defined Benefit Plan Disclosure [Line Items] | ||
Service cost | 0.5 | 0.5 |
Interest cost | 0.9 | 0.9 |
Expected return on plan assets | (0.2) | (0.2) |
Amortization of prior service cost (credit) | (0.1) | (0.2) |
Amortization of actuarial loss | 0.4 | 0.5 |
Total | $ 1.5 | $ 1.5 |
Benefit Plans (Defined Contribu
Benefit Plans (Defined Contribution Retirement Plans) (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
401(k) costs | $ 6.5 | $ 6.2 |
IPL [Member] | ||
401(k) costs | 3.4 | 3.1 |
WPL [Member] | ||
401(k) costs | $ 2.9 | $ 2.8 |
Benefit Plans (Recognized Compe
Benefit Plans (Recognized Compensation Expense And Income Tax Benefits) (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Compensation expense | $ 3.2 | $ 5.3 |
Income tax benefits | 1.3 | 2.2 |
IPL [Member] | ||
Compensation expense | 1.7 | 2.8 |
Income tax benefits | 0.7 | 1.1 |
WPL [Member] | ||
Compensation expense | 1.4 | 2.3 |
Income tax benefits | $ 0.5 | $ 0.9 |
Benefit Plans (Summary Of Perfo
Benefit Plans (Summary Of Performance Shares and Performance Units Activity) (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Performance Shares [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | ||
Nonvested, January 1 (in shares/awards) | 257,599 | 288,430 |
Granted (in shares/awards) | 63,804 | 67,552 |
Vested (in shares/awards) | (99,438) | (98,186) |
Forfeited (in shares/awards) | 0 | (1,230) |
Nonvested, March 31 (in shares/awards) | 221,965 | 256,566 |
Performance Units [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | ||
Nonvested, January 1 (in shares/awards) | 93,320 | 116,412 |
Granted (in shares/awards) | 21,558 | 23,918 |
Vested (in shares/awards) | (37,395) | (42,760) |
Forfeited (in shares/awards) | (497) | (764) |
Nonvested, March 31 (in shares/awards) | 76,986 | 96,806 |
2014 Grant [Member] | Performance Shares [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | ||
Vested (in shares/awards) | (99,438) | |
Vested percentage of the target | 147.50% | |
Aggregate payout value | $ 5.6 | |
Payout - cash | $ 5.1 | |
Payout - common stock shares issued (in shares) | 5,185 | |
2014 Grant [Member] | Performance Units [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | ||
Vested (in shares/awards) | (37,395) | |
Vested percentage of the target | 147.50% | |
Aggregate payout value | $ 1.5 | |
Payout - cash | $ 1.5 | |
2013 Grant [Member] | Performance Shares [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | ||
Vested (in shares/awards) | (98,186) | |
Vested percentage of the target | 165.00% | |
Aggregate payout value | $ 5.1 | |
Payout - cash | $ 2.9 | |
Payout - common stock shares issued (in shares) | 22,408 | |
2013 Grant [Member] | Performance Units [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | ||
Vested (in shares/awards) | (42,760) | |
Vested percentage of the target | 165.00% | |
Aggregate payout value | $ 1.7 | |
Payout - cash | $ 1.7 |
Benefit Plans (Fair Values Of N
Benefit Plans (Fair Values Of Nonvested Performance Shares And Performance Units) (Details) - $ / shares | 3 Months Ended | |||
Mar. 31, 2017 | Dec. 31, 2016 | Mar. 31, 2016 | Dec. 31, 2015 | |
Performance Shares [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Nonvested awards (in shares/awards) | 221,965 | 257,599 | 256,566 | 288,430 |
Performance Units [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Nonvested awards (in shares/awards) | 76,986 | 93,320 | 96,806 | 116,412 |
2017 Grant [Member] | Performance Shares [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Nonvested awards (in shares/awards) | 63,804 | |||
Alliant Energy common stock closing price on March 31, 2017 (in dollars per share) | $ 39.61 | |||
Estimated payout percentage based on performance criteria | 100.00% | |||
Fair values of each nonvested award (in dollars per share) | $ 39.61 | |||
2017 Grant [Member] | Performance Units [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Nonvested awards (in shares/awards) | 21,061 | |||
Alliant Energy common stock closing price on March 31, 2017 (in dollars per share) | $ 39.61 | |||
Estimated payout percentage based on performance criteria | 100.00% | |||
Fair values of each nonvested award (in dollars per share) | $ 39.61 | |||
2016 Grant [Member] | Performance Shares [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Nonvested awards (in shares/awards) | 67,355 | |||
Alliant Energy common stock closing price on March 31, 2017 (in dollars per share) | $ 39.61 | |||
Estimated payout percentage based on performance criteria | 160.00% | |||
Fair values of each nonvested award (in dollars per share) | $ 63.38 | |||
2016 Grant [Member] | Performance Units [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Nonvested awards (in shares/awards) | 22,657 | |||
Alliant Energy common stock closing price on March 31, 2017 (in dollars per share) | $ 39.61 | |||
Estimated payout percentage based on performance criteria | 160.00% | |||
Fair values of each nonvested award (in dollars per share) | $ 63.38 | |||
2015 Grant [Member] | Performance Shares [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Nonvested awards (in shares/awards) | 90,806 | |||
Alliant Energy common stock closing price on March 31, 2017 (in dollars per share) | $ 39.61 | |||
Estimated payout percentage based on performance criteria | 130.00% | |||
Fair values of each nonvested award (in dollars per share) | $ 51.49 | |||
2015 Grant [Member] | Performance Units [Member] | ||||
Defined Benefit Plan Disclosure [Line Items] | ||||
Nonvested awards (in shares/awards) | 33,268 | |||
Alliant Energy common stock closing price on grant date (in dollars per share) | $ 32.55 | |||
Estimated payout percentage based on performance criteria | 130.00% | |||
Fair values of each nonvested award (in dollars per share) | $ 42.32 |
Benefit Plans (Summary Of Restr
Benefit Plans (Summary Of Restricted Stock and Restricted Stock Units Activity) (Details) - $ / shares | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Performance Restricted Stock Unit [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | ||
Nonvested, January 1 (in shares/awards) | 67,355 | 0 |
Nonvested, January 1, weighted average grant date fair value (in dollars per share) | $ 33.96 | $ 0 |
Granted (in shares/awards) | 63,804 | 67,552 |
Granted, weighted average grant date fair value (in dollars per share) | $ 39.11 | $ 33.93 |
Forfeited (in shares/awards) | 0 | (1,230) |
Forfeited, weighted average grant date fair value (in dollars per share) | $ 0 | $ 33.90 |
Nonvested, March 31 (in shares/awards) | 131,159 | 66,322 |
Nonvested, March 31, weighted average grant date fair value (in dollars per share) | $ 36.46 | $ 33.93 |
Restricted Stock Units [Member] | ||
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested [Roll Forward] | ||
Nonvested, January 1 (in shares/awards) | 57,736 | 0 |
Granted (in shares/awards) | 54,688 | 57,904 |
Forfeited (in shares/awards) | 0 | (1,054) |
Nonvested, March 31 (in shares/awards) | 112,424 | 56,850 |
Fair Value Measurements (Narrat
Fair Value Measurements (Narrative) (Details) | 3 Months Ended |
Mar. 31, 2017 | |
IPL [Member] | |
Cumulative preferred stock rate | 5.10% |
Fair Value Measurements (Fair V
Fair Value Measurements (Fair Value Measurements) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
Assets: | ||
Deferred proceeds | $ 149 | $ 211.1 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 4,771.2 | 4,799 |
Cumulative preferred stock of IPL | 202.6 | 194.8 |
IPL [Member] | ||
Assets: | ||
Deferred proceeds | 149 | 211.1 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 2,342.1 | 2,352.3 |
Cumulative preferred stock of IPL | 202.6 | 194.8 |
WPL [Member] | ||
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 1,790.9 | 1,807.4 |
Commodity Contracts [Member] | ||
Assets: | ||
Derivatives | 13.3 | 41.4 |
Liabilities and Equity: | ||
Derivatives | 45.3 | 28.6 |
Commodity Contracts [Member] | IPL [Member] | ||
Assets: | ||
Derivatives | 8.8 | 20.8 |
Liabilities and Equity: | ||
Derivatives | 16.3 | 8.3 |
Commodity Contracts [Member] | WPL [Member] | ||
Assets: | ||
Derivatives | 4.5 | 20.6 |
Liabilities and Equity: | ||
Derivatives | 29 | 20.3 |
Level 1 [Member] | ||
Assets: | ||
Deferred proceeds | 0 | 0 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 0 | 0 |
Cumulative preferred stock of IPL | 202.6 | 194.8 |
Level 1 [Member] | IPL [Member] | ||
Assets: | ||
Deferred proceeds | 0 | 0 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 0 | 0 |
Cumulative preferred stock of IPL | 202.6 | 194.8 |
Level 1 [Member] | WPL [Member] | ||
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 0 | 0 |
Level 1 [Member] | Commodity Contracts [Member] | ||
Assets: | ||
Derivatives | 0 | 0 |
Liabilities and Equity: | ||
Derivatives | 0 | 0 |
Level 1 [Member] | Commodity Contracts [Member] | IPL [Member] | ||
Assets: | ||
Derivatives | 0 | 0 |
Liabilities and Equity: | ||
Derivatives | 0 | 0 |
Level 1 [Member] | Commodity Contracts [Member] | WPL [Member] | ||
Assets: | ||
Derivatives | 0 | 0 |
Liabilities and Equity: | ||
Derivatives | 0 | 0 |
Level 2 [Member] | ||
Assets: | ||
Deferred proceeds | 0 | 0 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 4,768.3 | 4,795.7 |
Cumulative preferred stock of IPL | 0 | 0 |
Level 2 [Member] | IPL [Member] | ||
Assets: | ||
Deferred proceeds | 0 | 0 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 2,342.1 | 2,352.3 |
Cumulative preferred stock of IPL | 0 | 0 |
Level 2 [Member] | WPL [Member] | ||
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 1,790.9 | 1,807.4 |
Level 2 [Member] | Commodity Contracts [Member] | ||
Assets: | ||
Derivatives | 1.7 | 4.6 |
Liabilities and Equity: | ||
Derivatives | 0.8 | 0.5 |
Level 2 [Member] | Commodity Contracts [Member] | IPL [Member] | ||
Assets: | ||
Derivatives | 1.3 | 2.8 |
Liabilities and Equity: | ||
Derivatives | 0.5 | 0.4 |
Level 2 [Member] | Commodity Contracts [Member] | WPL [Member] | ||
Assets: | ||
Derivatives | 0.4 | 1.8 |
Liabilities and Equity: | ||
Derivatives | 0.3 | 0.1 |
Level 3 [Member] | ||
Assets: | ||
Deferred proceeds | 149 | 211.1 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 2.9 | 3.3 |
Cumulative preferred stock of IPL | 0 | 0 |
Level 3 [Member] | IPL [Member] | ||
Assets: | ||
Deferred proceeds | 149 | 211.1 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 0 | 0 |
Cumulative preferred stock of IPL | 0 | 0 |
Level 3 [Member] | WPL [Member] | ||
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 0 | 0 |
Level 3 [Member] | Commodity Contracts [Member] | ||
Assets: | ||
Derivatives | 11.6 | 36.8 |
Liabilities and Equity: | ||
Derivatives | 44.5 | 28.1 |
Level 3 [Member] | Commodity Contracts [Member] | IPL [Member] | ||
Assets: | ||
Derivatives | 7.5 | 18 |
Liabilities and Equity: | ||
Derivatives | 15.8 | 7.9 |
Level 3 [Member] | Commodity Contracts [Member] | WPL [Member] | ||
Assets: | ||
Derivatives | 4.1 | 18.8 |
Liabilities and Equity: | ||
Derivatives | 28.7 | 20.2 |
Carrying Amount [Member] | ||
Assets: | ||
Deferred proceeds | 149 | 211.1 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 4,320.7 | 4,320.2 |
Cumulative preferred stock of IPL | 200 | 200 |
Carrying Amount [Member] | IPL [Member] | ||
Assets: | ||
Deferred proceeds | 149 | 211.1 |
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 2,154 | 2,153.5 |
Cumulative preferred stock of IPL | 200 | 200 |
Carrying Amount [Member] | WPL [Member] | ||
Liabilities and Equity: | ||
Long-term debt (including current maturities) | 1,535.5 | 1,535.2 |
Carrying Amount [Member] | Commodity Contracts [Member] | ||
Assets: | ||
Derivatives | 13.3 | 41.4 |
Liabilities and Equity: | ||
Derivatives | 45.3 | 28.6 |
Carrying Amount [Member] | Commodity Contracts [Member] | IPL [Member] | ||
Assets: | ||
Derivatives | 8.8 | 20.8 |
Liabilities and Equity: | ||
Derivatives | 16.3 | 8.3 |
Carrying Amount [Member] | Commodity Contracts [Member] | WPL [Member] | ||
Assets: | ||
Derivatives | 4.5 | 20.6 |
Liabilities and Equity: | ||
Derivatives | $ 29 | $ 20.3 |
Fair Value Measurements (Fair63
Fair Value Measurements (Fair Value Measurements Using Significant Unobservable Inputs) (Details) - USD ($) $ in Millions | 3 Months Ended | ||
Mar. 31, 2017 | Mar. 31, 2016 | ||
Commodity Contracts [Member] | |||
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | |||
Beginning balance | $ 8.7 | $ (32.7) | |
Total net losses included in changes in net assets (realized/unrealized) | (35.2) | (31.4) | |
Transfers into Level 3 | 0 | 0.9 | |
Sales | (0.1) | (0.6) | |
Settlements | (6.3) | (2.1) | |
Ending balance | (32.9) | (65.9) | |
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 | (33.7) | (30) | |
Commodity Contracts [Member] | IPL [Member] | |||
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | |||
Beginning balance | 10.1 | (1.9) | |
Total net losses included in changes in net assets (realized/unrealized) | (12.7) | (7.6) | |
Transfers into Level 3 | 0 | 0.5 | |
Sales | (0.1) | (0.6) | |
Settlements | (5.6) | (3.5) | |
Ending balance | (8.3) | (13.1) | |
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 | (11.4) | (6.6) | |
Commodity Contracts [Member] | WPL [Member] | |||
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | |||
Beginning balance | (1.4) | (30.8) | |
Total net losses included in changes in net assets (realized/unrealized) | (22.5) | (23.8) | |
Transfers into Level 3 | 0 | 0.4 | |
Settlements | (0.7) | 1.4 | |
Ending balance | (24.6) | (52.8) | |
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 | (22.3) | (23.4) | |
Deferred Proceeds [Member] | |||
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | |||
Beginning balance | 211.1 | 172 | |
Total net losses included in changes in net assets (realized/unrealized) | 0 | 0 | |
Transfers into Level 3 | 0 | 0 | |
Sales | 0 | 0 | |
Settlements | [1] | (62.1) | (17.8) |
Ending balance | 149 | 154.2 | |
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 | 0 | 0 | |
Deferred Proceeds [Member] | IPL [Member] | |||
Fair Value, Assets and Liabilities, Net, Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] | |||
Beginning balance | 211.1 | 172 | |
Total net losses included in changes in net assets (realized/unrealized) | 0 | 0 | |
Transfers into Level 3 | 0 | 0 | |
Sales | 0 | 0 | |
Settlements | [1] | (62.1) | (17.8) |
Ending balance | 149 | 154.2 | |
The amount of total net losses for the period included in changes in net assets attributable to the change in unrealized losses relating to assets and liabilities held at March 31 | $ 0 | $ 0 | |
[1] | Settlements related to deferred proceeds are due to the change in the carrying amount of receivables sold less the allowance for doubtful accounts associated with the receivables sold and cash amounts received from the receivables sold. |
Fair Value Measurements (Fair64
Fair Value Measurements (Fair Value Of Net Derivative Assets (Liabilities)) (Details) - Commodity Contracts [Member] - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 | Mar. 31, 2016 | Dec. 31, 2015 |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative assets | $ (32.9) | $ 8.7 | $ (65.9) | $ (32.7) |
Excluding Financial Transmission Rights [Member] | ||||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative liabilities | 37 | 2.3 | ||
Financial Transmission Rights [Member] | ||||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative assets | 4.1 | 11 | ||
IPL [Member] | ||||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative assets | (8.3) | 10.1 | (13.1) | (1.9) |
IPL [Member] | Excluding Financial Transmission Rights [Member] | ||||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative assets | 0.1 | |||
Fair value, net derivative liabilities | 11.6 | |||
IPL [Member] | Financial Transmission Rights [Member] | ||||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative assets | 3.3 | 10 | ||
WPL [Member] | ||||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative assets | (24.6) | (1.4) | $ (52.8) | $ (30.8) |
WPL [Member] | Excluding Financial Transmission Rights [Member] | ||||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative liabilities | 25.4 | 2.4 | ||
WPL [Member] | Financial Transmission Rights [Member] | ||||
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] | ||||
Fair value, net derivative assets | $ 0.8 | $ 1 |
Derivative Instruments (Notiona
Derivative Instruments (Notional Amounts Of Derivative Instruments) (Details) - Commodity [Member] gal in Thousands, T in Thousands, MWh in Thousands, Dekatherms in Thousands | 3 Months Ended |
Mar. 31, 2017DekathermsMWhTgal | |
Electricity (MWhs) [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in MWhs) | 2,304 |
Electricity (MWhs) [Member] | IPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in MWhs) | 0 |
Electricity (MWhs) [Member] | WPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in MWhs) | 2,304 |
FTRs (MWhs) [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in MWhs) | 3,537 |
FTRs (MWhs) [Member] | IPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in MWhs) | 2,229 |
FTRs (MWhs) [Member] | WPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in MWhs) | 1,308 |
Natural Gas (Dths) [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Dths) | Dekatherms | 160,048 |
Natural Gas (Dths) [Member] | IPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Dths) | Dekatherms | 72,924 |
Natural Gas (Dths) [Member] | WPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Dths) | Dekatherms | 87,124 |
Coal (Tons) [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Tons) | T | 4,113 |
Coal (Tons) [Member] | IPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Tons) | T | 1,680 |
Coal (Tons) [Member] | WPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Tons) | T | 2,433 |
Diesel Fuel (Gallons) [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Gallons) | gal | 5,796 |
Diesel Fuel (Gallons) [Member] | IPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Gallons) | gal | 0 |
Diesel Fuel (Gallons) [Member] | WPL [Member] | |
Notional Amount of Derivatives [Line Items] | |
Notional unit amount of derivatives (in Gallons) | gal | 5,796 |
Derivative Instruments (Fair Va
Derivative Instruments (Fair Value Of Financial Instruments) (Details) - Commodity Contracts [Member] - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
Derivatives, Fair Value [Line Items] | ||
Current derivative assets | $ 12.2 | $ 29.4 |
Non-current derivative assets | 1.1 | 12 |
Current derivative liabilities | 13.4 | 13.3 |
Non-current derivative liabilities | 31.9 | 15.3 |
IPL [Member] | ||
Derivatives, Fair Value [Line Items] | ||
Current derivative assets | 8.2 | 19.1 |
Non-current derivative assets | 0.6 | 1.7 |
Current derivative liabilities | 2.9 | 2.7 |
Non-current derivative liabilities | 13.4 | 5.6 |
WPL [Member] | ||
Derivatives, Fair Value [Line Items] | ||
Current derivative assets | 4 | 10.3 |
Non-current derivative assets | 0.5 | 10.3 |
Current derivative liabilities | 10.5 | 10.6 |
Non-current derivative liabilities | $ 18.5 | $ 9.7 |
Commitments And Contingencies67
Commitments And Contingencies (Narrative) (Details) $ in Millions | 3 Months Ended |
Mar. 31, 2017USD ($) | |
Commitments and Contingencies [Line Items] | |
Minimum future commitments | $ 2,387 |
Present value abandonment obligation | 31 |
IPL [Member] | |
Commitments and Contingencies [Line Items] | |
Minimum future commitments | 1,785 |
Maximum indemnification limit | 17 |
WPL [Member] | |
Commitments and Contingencies [Line Items] | |
Minimum future commitments | 587 |
Capital Purchase Obligation [Member] | |
Commitments and Contingencies [Line Items] | |
Minimum future commitments | 36 |
Capital Purchase Obligation [Member] | IPL [Member] | |
Commitments and Contingencies [Line Items] | |
Minimum future commitments | 5 |
Capital Purchase Obligation [Member] | WPL [Member] | |
Commitments and Contingencies [Line Items] | |
Minimum future commitments | 31 |
Environmental Issue [Member] | IPL [Member] | |
Commitments and Contingencies [Line Items] | |
Environmental mitigation projects to be completed, value | 6 |
Environmental Issue [Member] | WPL [Member] | |
Commitments and Contingencies [Line Items] | |
Environmental mitigation projects to be completed, value | $ 7 |
Workforce Subject to Collective Bargaining Arrangements [Member] | |
Commitments and Contingencies [Line Items] | |
Employees covered by collective bargaining agreement | 56.00% |
Workforce Subject to Collective Bargaining Arrangements [Member] | IPL [Member] | |
Commitments and Contingencies [Line Items] | |
Employees covered by collective bargaining agreement | 64.00% |
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] | |
Commitments and Contingencies [Line Items] | |
Employees covered by collective bargaining agreement | 19.00% |
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] | IPL [Member] | |
Commitments and Contingencies [Line Items] | |
Employees covered by collective bargaining agreement | 45.00% |
Commitments And Contingencies68
Commitments And Contingencies (Operating Expense Purchase Obligations) (Details) $ in Millions | 3 Months Ended | |
Mar. 31, 2017USD ($) | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | $ 2,387 | |
Individual commitments incurred | 1 | |
IPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 1,785 | |
Individual commitments incurred | 1 | |
WPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 587 | |
Individual commitments incurred | 1 | |
Purchased power [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 1,372 | [1] |
Purchased power [Member] | IPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 1,266 | [1] |
Purchased power [Member] | WPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 106 | [1] |
Natural gas [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 812 | |
Natural gas [Member] | IPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 426 | |
Natural gas [Member] | WPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 386 | |
Coal [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 165 | [2] |
Coal [Member] | IPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 73 | [2] |
Coal [Member] | WPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 92 | [2] |
Other [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 38 | [3] |
Other [Member] | IPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | 20 | [3] |
Other [Member] | WPL [Member] | ||
Commitments and Contingencies [Line Items] | ||
Minimum future commitments | $ 3 | [3] |
[1] | Includes payments required by purchased power agreements for capacity rights and minimum quantities of MWhs required to be purchased. | |
[2] | Corporate Services entered into system-wide coal contracts on behalf of IPL and WPL that include minimum future commitments. These commitments were assigned to IPL and WPL based on information available as of March 31, 2017 regarding expected future usage, which is subject to change. | |
[3] | Includes individual commitments incurred during the normal course of business that exceeded $1 million at March 31, 2017. |
Commitments And Contingencies69
Commitments And Contingencies (MPG Site Estimated Future Costs And Recorded Liabilities) (Details) - Manufactured Gas Plant Sites [Member] $ in Millions | 3 Months Ended |
Mar. 31, 2017USD ($) | |
Commitments and Contingencies [Line Items] | |
Minimum range of estimated future costs | $ 12 |
Maximum range of estimated future costs | 31 |
Current and non-current environmental liabilities | 17 |
IPL [Member] | |
Commitments and Contingencies [Line Items] | |
Minimum range of estimated future costs | 10 |
Maximum range of estimated future costs | 28 |
Current and non-current environmental liabilities | $ 14 |
Segments Of Business (Schedule
Segments Of Business (Schedule Of Segments Of Business) (Details) - USD ($) $ in Millions | 3 Months Ended | ||
Mar. 31, 2017 | Mar. 31, 2016 | ||
Segment Reporting Information [Line Items] | |||
Operating revenues | $ 853.9 | $ 843.8 | |
Operating income (loss) | 142.9 | 145.9 | |
Income from continuing operations, net of tax | 99 | 97.6 | |
Income (loss) from discontinued operations, net of tax | 1.4 | (1.1) | |
Net income attributable to common shareowners | 100.4 | 96.5 | |
IPL [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 450.5 | 458.7 | |
Operating income (loss) | 49.6 | 62 | |
Net income attributable to common shareowners | 37.2 | 45.6 | |
WPL [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 393.1 | 375.6 | |
Operating income (loss) | 86 | 78.8 | |
Net income attributable to common shareowners | 45.5 | 46.5 | |
Electric [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | [1] | 677.6 | 668.9 |
Operating income (loss) | [1] | 107.2 | 109.8 |
Electric [Member] | IPL [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 356.2 | 361.6 | |
Operating income (loss) | 33.8 | 43.4 | |
Electric [Member] | WPL [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 321.4 | 307.3 | |
Operating income (loss) | 73.4 | 66.4 | |
Gas [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | [1] | 154.3 | 152.2 |
Operating income (loss) | [1] | 28 | 28.8 |
Gas [Member] | IPL [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 83.1 | 84.2 | |
Operating income (loss) | 14.4 | 15.8 | |
Gas [Member] | WPL [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 71.2 | 68 | |
Operating income (loss) | 13.6 | 13 | |
Other Utilities [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | [1] | 11.7 | 13.2 |
Operating income (loss) | [1] | 0.4 | 2.2 |
Other Utilities [Member] | IPL [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 11.2 | 12.9 | |
Operating income (loss) | 1.4 | 2.8 | |
Other Utilities [Member] | WPL [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 0.5 | 0.3 | |
Operating income (loss) | (1) | (0.6) | |
Utility Business [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | [1] | 843.6 | 834.3 |
Operating income (loss) | [1] | 135.6 | 140.8 |
Income from continuing operations, net of tax | [1] | 89.6 | 92.1 |
Income (loss) from discontinued operations, net of tax | [1] | 0 | 0 |
Net income attributable to common shareowners | [1] | 89.6 | 92.1 |
Non-Regulated [Member] | Other Segments [Member] | |||
Segment Reporting Information [Line Items] | |||
Operating revenues | 10.3 | 9.5 | |
Operating income (loss) | 7.3 | 5.1 | |
Income from continuing operations, net of tax | 9.4 | 5.5 | |
Income (loss) from discontinued operations, net of tax | 1.4 | (1.1) | |
Net income attributable to common shareowners | $ 10.8 | $ 4.4 | |
[1] | Alliant Energy’s utility business segments include: a) utility electric operations, which include Alliant Energy’s entire investment in ATC; b) utility gas operations; and c) utility other, which includes steam operations and the unallocated portions of the utility business. |
Related Parties (Narrative) (De
Related Parties (Narrative) (Details) - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
WPL [Member] | WPL Owed ATC, LLC [Member] | ||
Related Party Transactions [Line Items] | ||
Net amounts owed | $ 8 | $ 8 |
Related Parties (Service Agreem
Related Parties (Service Agreements) (Details) - Corporate Services [Member] - Subsidiary of Common Parent [Member] - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Administrative and General Services Billings [Member] | IPL [Member] | ||
Related Party Transactions [Line Items] | ||
Amounts billed between related parties | $ 39 | $ 38 |
Administrative and General Services Billings [Member] | WPL [Member] | ||
Related Party Transactions [Line Items] | ||
Amounts billed between related parties | 31 | 33 |
Sales Credited [Member] | IPL [Member] | ||
Related Party Transactions [Line Items] | ||
Amounts billed between related parties | 2 | 1 |
Sales Credited [Member] | WPL [Member] | ||
Related Party Transactions [Line Items] | ||
Amounts billed between related parties | 0 | 1 |
Purchases Billed [Member] | IPL [Member] | ||
Related Party Transactions [Line Items] | ||
Amounts billed between related parties | 66 | 96 |
Purchases Billed [Member] | WPL [Member] | ||
Related Party Transactions [Line Items] | ||
Amounts billed between related parties | $ 34 | $ 19 |
Related Parties (Net Intercompa
Related Parties (Net Intercompany Payables) (Details) - Subsidiary of Common Parent [Member] - Corporate Services [Member] - USD ($) $ in Millions | Mar. 31, 2017 | Dec. 31, 2016 |
IPL [Member] | ||
Related Party Transactions [Line Items] | ||
Net amounts owed | $ 103 | $ 104 |
WPL [Member] | ||
Related Party Transactions [Line Items] | ||
Net amounts owed | $ 65 | $ 72 |
Related Parties (Amounts Billed
Related Parties (Amounts Billed Between Parties) (Details) - ATC, LLC [Member] - WPL [Member] - Equity Method Investment [Member] - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
ATC, LLC Billings To WPL [Member] | ||
Related Party Transactions [Line Items] | ||
Amounts billed between related parties | $ 26 | $ 27 |
WPL Billings To ATC, LLC [Member] | ||
Related Party Transactions [Line Items] | ||
Amounts billed between related parties | $ 3 | $ 3 |
Discontinued Operations (Compon
Discontinued Operations (Components Of Discontinued Operations In Consolidated Statements Of Income (Details) - USD ($) $ in Millions | 3 Months Ended | |
Mar. 31, 2017 | Mar. 31, 2016 | |
Discontinued Operations and Disposal Groups [Abstract] | ||
Operating expenses (income) | $ (2.3) | $ 1.9 |
Income (loss) before income taxes | 2.3 | (1.9) |
Income tax expense (benefit) | 0.9 | (0.8) |
Income (loss) from discontinued operations, net of tax | $ 1.4 | $ (1.1) |