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Property, Plant and Equipment | 9 Months Ended
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Sep. 30, 2018
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT Utility - Natural Gas-Fired Generation Project - WPL’s West Riverside Energy Center - WPL is currently constructing West Riverside, an approximate 730 MW natural gas-fired combined-cycle EGU. Construction began in 2016 and is currently expected to be completed by the end of 2019. As of September 30, 2018, Alliant Energy and WPL recorded capitalized expenditures of $438 million and AFUDC of $35 million for West Riverside in “Property, plant and equipment, net” on their balance sheets. These capital expenditures reflect WPL’s portion of West Riverside. Certain electric cooperatives, which currently have wholesale power supply agreements with WPL, acquired approximately 60 MW of West Riverside in January 2018, and are funding their share of capital expenditures during construction. As part of the electric cooperatives’ acquisitions, the current wholesale power supply agreements with the various electric cooperatives were extended by at least four years until 2026 with automatic continuation of such agreements unless terminated by either party, with a five-year notice requirement. Wind Generation - IPL’s Expansion of Wind Generation - IPL currently plans to add up to 1,000 MW of new wind generation to its existing generation portfolio. These wind projects are expected to be placed into service in 2019 and 2020. As of September 30, 2018, Alliant Energy and IPL recorded capitalized expenditures of $645 million and AFUDC of $33 million for this expansion of wind generation in “Property, plant and equipment, net” on their balance sheets. WPL’s Acquisition of Forward Wind Energy Center (FWEC) - In January 2018 and March 2018, WPL received approval from FERC and the PSCW, respectively, to acquire a partial ownership interest in the assets of FWEC, which is a 129 MW wind farm located in Wisconsin. In April 2018, WPL acquired 55 MW of the FWEC wind farm for approximately $74 million. As of the closing date, the estimated fair value of the assets purchased and the liabilities assumed by WPL were as follows (in millions):
Property, plant and equipment, net |  | $81 |
Liabilities | 7 |
Net assets acquired |  | $74 |
IPL [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT Utility - Natural Gas-Fired Generation Project - WPL’s West Riverside Energy Center - WPL is currently constructing West Riverside, an approximate 730 MW natural gas-fired combined-cycle EGU. Construction began in 2016 and is currently expected to be completed by the end of 2019. As of September 30, 2018, Alliant Energy and WPL recorded capitalized expenditures of $438 million and AFUDC of $35 million for West Riverside in “Property, plant and equipment, net” on their balance sheets. These capital expenditures reflect WPL’s portion of West Riverside. Certain electric cooperatives, which currently have wholesale power supply agreements with WPL, acquired approximately 60 MW of West Riverside in January 2018, and are funding their share of capital expenditures during construction. As part of the electric cooperatives’ acquisitions, the current wholesale power supply agreements with the various electric cooperatives were extended by at least four years until 2026 with automatic continuation of such agreements unless terminated by either party, with a five-year notice requirement. Wind Generation - IPL’s Expansion of Wind Generation - IPL currently plans to add up to 1,000 MW of new wind generation to its existing generation portfolio. These wind projects are expected to be placed into service in 2019 and 2020. As of September 30, 2018, Alliant Energy and IPL recorded capitalized expenditures of $645 million and AFUDC of $33 million for this expansion of wind generation in “Property, plant and equipment, net” on their balance sheets.
WPL [Member] |
Property, Plant and Equipment [Line Items] |
Property, Plant and Equipment | PROPERTY, PLANT AND EQUIPMENT Utility - Natural Gas-Fired Generation Project - WPL’s West Riverside Energy Center - WPL is currently constructing West Riverside, an approximate 730 MW natural gas-fired combined-cycle EGU. Construction began in 2016 and is currently expected to be completed by the end of 2019. As of September 30, 2018, Alliant Energy and WPL recorded capitalized expenditures of $438 million and AFUDC of $35 million for West Riverside in “Property, plant and equipment, net” on their balance sheets. These capital expenditures reflect WPL’s portion of West Riverside. Certain electric cooperatives, which currently have wholesale power supply agreements with WPL, acquired approximately 60 MW of West Riverside in January 2018, and are funding their share of capital expenditures during construction. As part of the electric cooperatives’ acquisitions, the current wholesale power supply agreements with the various electric cooperatives were extended by at least four years until 2026 with automatic continuation of such agreements unless terminated by either party, with a five-year notice requirement. Wind Generation - IPL’s Expansion of Wind Generation - IPL currently plans to add up to 1,000 MW of new wind generation to its existing generation portfolio. These wind projects are expected to be placed into service in 2019 and 2020. As of September 30, 2018, Alliant Energy and IPL recorded capitalized expenditures of $645 million and AFUDC of $33 million for this expansion of wind generation in “Property, plant and equipment, net” on their balance sheets. WPL’s Acquisition of Forward Wind Energy Center (FWEC) - In January 2018 and March 2018, WPL received approval from FERC and the PSCW, respectively, to acquire a partial ownership interest in the assets of FWEC, which is a 129 MW wind farm located in Wisconsin. In April 2018, WPL acquired 55 MW of the FWEC wind farm for approximately $74 million. As of the closing date, the estimated fair value of the assets purchased and the liabilities assumed by WPL were as follows (in millions):
Property, plant and equipment, net |  | $81 |
Liabilities | 7 |
Net assets acquired |  | $74 |

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -URI http://asc.fasb.org/topic&trid=2155823 + Details
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