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Property, Plant and Equipment | 12 Months Ended
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Dec. 31, 2019
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT At December 31, details of property, plant and equipment on the balance sheets were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Utility: |  |  |  |  |  |  |  |  |  |  |
Electric plant: |  |  |  |  |  |  |  |  |  |  |
Generation in service |  | $7,625.3 |  |  |  | $6,800.6 |  |  |  | $4,432.4 |  |  |  | $3,610.4 |  |  |  | $3,192.9 |  |  |  | $3,190.2 |
Distribution in service | 5,783.3 |  |  | 5,452.2 |  |  | 3,190.0 |  |  | 3,023.7 |  |  | 2,593.3 |  |  | 2,428.5 |
Other in service | 456.0 |  |  | 410.8 |  |  | 298.6 |  |  | 260.4 |  |  | 157.4 |  |  | 150.4 |
Total electric plant | 13,864.6 |  |  | 12,663.6 |  |  | 7,921.0 |  |  | 6,894.5 |  |  | 5,943.6 |  |  | 5,769.1 |
Gas plant in service | 1,462.7 |  |  | 1,387.6 |  |  | 801.5 |  |  | 763.1 |  |  | 661.2 |  |  | 624.5 |
Other plant in service | 519.7 |  |  | 513.2 |  |  | 344.7 |  |  | 322.4 |  |  | 175.0 |  |  | 190.8 |
Accumulated depreciation | (4,601.4 | ) |  | (4,314.6 | ) |  | (2,498.3 | ) |  | (2,294.7 | ) |  | (2,103.1 | ) |  | (2,019.9 | )
Net plant | 11,245.6 |  |  | 10,249.8 |  |  | 6,568.9 |  |  | 5,685.3 |  |  | 4,676.7 |  |  | 4,564.5 |
Leased Sheboygan Falls Energy Facility, net (a) | — |  |  | — |  |  | — |  |  | — |  |  | 32.3 |  |  | 38.1 |
Construction work in progress | 1,835.0 |  |  | 1,774.8 |  |  | 906.8 |  |  | 1,091.2 |  |  | 928.2 |  |  | 683.6 |
Other, net | 6.1 |  |  | 6.1 |  |  | 5.0 |  |  | 5.0 |  |  | 1.1 |  |  | 1.1 |
Total utility | 13,086.7 |  |  | 12,030.7 |  |  | 7,480.7 |  |  | 6,781.5 |  |  | 5,638.3 |  |  | 5,287.3 |
Non-utility and other: |  |  |  |  |  |  |  |  |  |  |
Non-utility Generation, net (b) | 82.9 |  |  | 86.9 |  |  | — |  |  | — |  |  | — |  |  | — |
Corporate Services and other, net (c) | 357.5 |  |  | 344.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total non-utility and other | 440.4 |  |  | 431.7 |  |  | — |  |  | — |  |  | — |  |  | — |
Total property, plant and equipment |  | $13,527.1 |  |  |  | $12,462.4 |  |  |  | $7,480.7 |  |  |  | $6,781.5 |  |  |  | $5,638.3 |  |  |  | $5,287.3 |
(a) | Less accumulated amortization of $88.7 million and $82.8 million for WPL as of December 31, 2019 and 2018, respectively. The Sheboygan Falls Energy Facility is eliminated from WPL upon consolidation and is included in the “Non-utility Generation, net” line within Alliant Energy’s consolidated property, plant and equipment.
(b) | Less accumulated depreciation of $58.5 million and $54.5 million for Alliant Energy as of December 31, 2019 and 2018, respectively.
(c) | Less accumulated depreciation of $172.4 million and $167.5 million for Alliant Energy as of December 31, 2019 and 2018, respectively.
AFUDC - AFUDC represents costs to finance construction additions, including a return on equity component and cost of debt component as required by regulatory accounting. The concurrent credit for the amount of AFUDC capitalized is recorded as “Allowance for funds used during construction” in the income statements. The amount of AFUDC generated by equity and debt components was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017
Equity |  | $65.5 |  |  |  | $51.4 |  |  |  | $33.6 |  |  |  | $35.2 |  |  |  | $28.6 |  |  |  | $21.1 |  |  |  | $30.3 |  |  |  | $22.8 |  |  |  | $12.5 |
Debt | 27.2 |  |  | 24.2 |  |  | 16.1 |  |  | 14.2 |  |  | 13.6 |  |  | 10.3 |  |  | 13.0 |  |  | 10.6 |  |  | 5.8 |
|  | $92.7 |  |  |  | $75.6 |  |  |  | $49.7 |  |  |  | $49.4 |  |  |  | $42.2 |  |  |  | $31.4 |  |  |  | $43.3 |  |  |  | $33.4 |  |  |  | $18.3 |
Non-utility and Other - The non-utility and other property, plant and equipment recorded on Alliant Energy’s balance sheets include the following: Non-utility Generation - The Sheboygan Falls Energy Facility was placed into service in 2005 and is depreciated using the straight-line method over a 35-year period. Corporate Services and Other - Property, plant and equipment related to Corporate Services include a customer billing and information system for IPL and WPL and other computer software, and the corporate headquarters building located in Madison, Wisconsin. The customer billing and information system is amortized using the straight-line method over a 12-year period. The majority of the remaining software is amortized over a 5-year period. Other property, plant and equipment include Transportation assets (a short-line railway in Iowa and a barge terminal on the Mississippi River). All Corporate Services and Other property, plant and equipment are depreciated using the straight-line method over periods ranging from 5 to 30 years. Transportation Acquisitions - In the first quarter of 2019, Alliant Energy, through its wholly-owned non-utility subsidiaries, completed acquisitions of freight management companies located in Cedar Rapids, Iowa and Stoughton, Wisconsin. These acquisitions were purchased for $21 million, including contingent consideration of $8 million, which was paid in January 2020. The purchase price was largely allocated to intangibles and the remainder was allocated to working capital and property.
IPL [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT At December 31, details of property, plant and equipment on the balance sheets were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Utility: |  |  |  |  |  |  |  |  |  |  |
Electric plant: |  |  |  |  |  |  |  |  |  |  |
Generation in service |  | $7,625.3 |  |  |  | $6,800.6 |  |  |  | $4,432.4 |  |  |  | $3,610.4 |  |  |  | $3,192.9 |  |  |  | $3,190.2 |
Distribution in service | 5,783.3 |  |  | 5,452.2 |  |  | 3,190.0 |  |  | 3,023.7 |  |  | 2,593.3 |  |  | 2,428.5 |
Other in service | 456.0 |  |  | 410.8 |  |  | 298.6 |  |  | 260.4 |  |  | 157.4 |  |  | 150.4 |
Total electric plant | 13,864.6 |  |  | 12,663.6 |  |  | 7,921.0 |  |  | 6,894.5 |  |  | 5,943.6 |  |  | 5,769.1 |
Gas plant in service | 1,462.7 |  |  | 1,387.6 |  |  | 801.5 |  |  | 763.1 |  |  | 661.2 |  |  | 624.5 |
Other plant in service | 519.7 |  |  | 513.2 |  |  | 344.7 |  |  | 322.4 |  |  | 175.0 |  |  | 190.8 |
Accumulated depreciation | (4,601.4 | ) |  | (4,314.6 | ) |  | (2,498.3 | ) |  | (2,294.7 | ) |  | (2,103.1 | ) |  | (2,019.9 | )
Net plant | 11,245.6 |  |  | 10,249.8 |  |  | 6,568.9 |  |  | 5,685.3 |  |  | 4,676.7 |  |  | 4,564.5 |
Leased Sheboygan Falls Energy Facility, net (a) | — |  |  | — |  |  | — |  |  | — |  |  | 32.3 |  |  | 38.1 |
Construction work in progress | 1,835.0 |  |  | 1,774.8 |  |  | 906.8 |  |  | 1,091.2 |  |  | 928.2 |  |  | 683.6 |
Other, net | 6.1 |  |  | 6.1 |  |  | 5.0 |  |  | 5.0 |  |  | 1.1 |  |  | 1.1 |
Total utility | 13,086.7 |  |  | 12,030.7 |  |  | 7,480.7 |  |  | 6,781.5 |  |  | 5,638.3 |  |  | 5,287.3 |
Non-utility and other: |  |  |  |  |  |  |  |  |  |  |
Non-utility Generation, net (b) | 82.9 |  |  | 86.9 |  |  | — |  |  | — |  |  | — |  |  | — |
Corporate Services and other, net (c) | 357.5 |  |  | 344.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total non-utility and other | 440.4 |  |  | 431.7 |  |  | — |  |  | — |  |  | — |  |  | — |
Total property, plant and equipment |  | $13,527.1 |  |  |  | $12,462.4 |  |  |  | $7,480.7 |  |  |  | $6,781.5 |  |  |  | $5,638.3 |  |  |  | $5,287.3 |
(a) | Less accumulated amortization of $88.7 million and $82.8 million for WPL as of December 31, 2019 and 2018, respectively. The Sheboygan Falls Energy Facility is eliminated from WPL upon consolidation and is included in the “Non-utility Generation, net” line within Alliant Energy’s consolidated property, plant and equipment.
(b) | Less accumulated depreciation of $58.5 million and $54.5 million for Alliant Energy as of December 31, 2019 and 2018, respectively.
(c) | Less accumulated depreciation of $172.4 million and $167.5 million for Alliant Energy as of December 31, 2019 and 2018, respectively.
AFUDC - AFUDC represents costs to finance construction additions, including a return on equity component and cost of debt component as required by regulatory accounting. The concurrent credit for the amount of AFUDC capitalized is recorded as “Allowance for funds used during construction” in the income statements. The amount of AFUDC generated by equity and debt components was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017
Equity |  | $65.5 |  |  |  | $51.4 |  |  |  | $33.6 |  |  |  | $35.2 |  |  |  | $28.6 |  |  |  | $21.1 |  |  |  | $30.3 |  |  |  | $22.8 |  |  |  | $12.5 |
Debt | 27.2 |  |  | 24.2 |  |  | 16.1 |  |  | 14.2 |  |  | 13.6 |  |  | 10.3 |  |  | 13.0 |  |  | 10.6 |  |  | 5.8 |
|  | $92.7 |  |  |  | $75.6 |  |  |  | $49.7 |  |  |  | $49.4 |  |  |  | $42.2 |  |  |  | $31.4 |  |  |  | $43.3 |  |  |  | $33.4 |  |  |  | $18.3 |
WPL [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT At December 31, details of property, plant and equipment on the balance sheets were as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2019 |  | 2018 |  | 2019 |  | 2018 |  | 2019 |  | 2018
Utility: |  |  |  |  |  |  |  |  |  |  |
Electric plant: |  |  |  |  |  |  |  |  |  |  |
Generation in service |  | $7,625.3 |  |  |  | $6,800.6 |  |  |  | $4,432.4 |  |  |  | $3,610.4 |  |  |  | $3,192.9 |  |  |  | $3,190.2 |
Distribution in service | 5,783.3 |  |  | 5,452.2 |  |  | 3,190.0 |  |  | 3,023.7 |  |  | 2,593.3 |  |  | 2,428.5 |
Other in service | 456.0 |  |  | 410.8 |  |  | 298.6 |  |  | 260.4 |  |  | 157.4 |  |  | 150.4 |
Total electric plant | 13,864.6 |  |  | 12,663.6 |  |  | 7,921.0 |  |  | 6,894.5 |  |  | 5,943.6 |  |  | 5,769.1 |
Gas plant in service | 1,462.7 |  |  | 1,387.6 |  |  | 801.5 |  |  | 763.1 |  |  | 661.2 |  |  | 624.5 |
Other plant in service | 519.7 |  |  | 513.2 |  |  | 344.7 |  |  | 322.4 |  |  | 175.0 |  |  | 190.8 |
Accumulated depreciation | (4,601.4 | ) |  | (4,314.6 | ) |  | (2,498.3 | ) |  | (2,294.7 | ) |  | (2,103.1 | ) |  | (2,019.9 | )
Net plant | 11,245.6 |  |  | 10,249.8 |  |  | 6,568.9 |  |  | 5,685.3 |  |  | 4,676.7 |  |  | 4,564.5 |
Leased Sheboygan Falls Energy Facility, net (a) | — |  |  | — |  |  | — |  |  | — |  |  | 32.3 |  |  | 38.1 |
Construction work in progress | 1,835.0 |  |  | 1,774.8 |  |  | 906.8 |  |  | 1,091.2 |  |  | 928.2 |  |  | 683.6 |
Other, net | 6.1 |  |  | 6.1 |  |  | 5.0 |  |  | 5.0 |  |  | 1.1 |  |  | 1.1 |
Total utility | 13,086.7 |  |  | 12,030.7 |  |  | 7,480.7 |  |  | 6,781.5 |  |  | 5,638.3 |  |  | 5,287.3 |
Non-utility and other: |  |  |  |  |  |  |  |  |  |  |
Non-utility Generation, net (b) | 82.9 |  |  | 86.9 |  |  | — |  |  | — |  |  | — |  |  | — |
Corporate Services and other, net (c) | 357.5 |  |  | 344.8 |  |  | — |  |  | — |  |  | — |  |  | — |
Total non-utility and other | 440.4 |  |  | 431.7 |  |  | — |  |  | — |  |  | — |  |  | — |
Total property, plant and equipment |  | $13,527.1 |  |  |  | $12,462.4 |  |  |  | $7,480.7 |  |  |  | $6,781.5 |  |  |  | $5,638.3 |  |  |  | $5,287.3 |
(a) | Less accumulated amortization of $88.7 million and $82.8 million for WPL as of December 31, 2019 and 2018, respectively. The Sheboygan Falls Energy Facility is eliminated from WPL upon consolidation and is included in the “Non-utility Generation, net” line within Alliant Energy’s consolidated property, plant and equipment.
(b) | Less accumulated depreciation of $58.5 million and $54.5 million for Alliant Energy as of December 31, 2019 and 2018, respectively.
(c) | Less accumulated depreciation of $172.4 million and $167.5 million for Alliant Energy as of December 31, 2019 and 2018, respectively.
AFUDC - AFUDC represents costs to finance construction additions, including a return on equity component and cost of debt component as required by regulatory accounting. The concurrent credit for the amount of AFUDC capitalized is recorded as “Allowance for funds used during construction” in the income statements. The amount of AFUDC generated by equity and debt components was as follows (in millions):
| Alliant Energy |  | IPL |  | WPL
| 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017
Equity |  | $65.5 |  |  |  | $51.4 |  |  |  | $33.6 |  |  |  | $35.2 |  |  |  | $28.6 |  |  |  | $21.1 |  |  |  | $30.3 |  |  |  | $22.8 |  |  |  | $12.5 |
Debt | 27.2 |  |  | 24.2 |  |  | 16.1 |  |  | 14.2 |  |  | 13.6 |  |  | 10.3 |  |  | 13.0 |  |  | 10.6 |  |  | 5.8 |
|  | $92.7 |  |  |  | $75.6 |  |  |  | $49.7 |  |  |  | $49.4 |  |  |  | $42.2 |  |  |  | $31.4 |  |  |  | $43.3 |  |  |  | $33.4 |  |  |  | $18.3 |

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- Definition The entire disclosure for long-lived, physical assets used in the normal conduct of business and not intended for resale. Includes, but is not limited to, accounting policies and methodology, roll forwards, depreciation, depletion and amortization expense, including composite depreciation, accumulated depreciation, depletion and amortization expense, useful lives and method used, income statement disclosures, assets held for sale and public utility disclosures. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -URI http://asc.fasb.org/topic&trid=2155823 + Details
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