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v3.21.2

Debt | 9 Months Ended
--- | ---
Sep. 30, 2021
Debt [Line Items] |
Debt | DEBT NOTE 7(a) Short-term Debt - In the third quarter of 2021, Alliant Energy, IPL and WPL reallocated credit facility capacity amounts to $500 million for Alliant Energy at the parent company level, $100 million for IPL and $400 million for WPL, within the $1 billion total commitment. Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):
September 30, 2021 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $316 |  | $— |  | $3
Weighted average interest rates | 0.2% |  | N/A |  | 0.1%
Available credit facility capacity | $684 |  | $100 |  | $397
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020
Maximum amount outstanding (based on daily outstanding balances) | $648 |  | $422 |  | $8 |  | $— |  | $320 |  | $139
Average amount outstanding (based on daily outstanding balances) | $560 |  | $252 |  | $— |  | $— |  | $221 |  | $83
Weighted average interest rates | 0.2% |  | 0.2% |  | 0.2% |  | N/A |  | 0.1% |  | 0.2%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $648 |  | $463 |  | $19 |  | $8 |  | $320 |  | $212
Average amount outstanding (based on daily outstanding balances) | $479 |  | $252 |  | $— |  | $— |  | $196 |  | $86
Weighted average interest rates | 0.2% |  | 1.1% |  | 0.2% |  | 0.5% |  | 0.1% |  | 1.2%
NOTE 7(b) Long-term Debt - In September 2021, WPL issued $300 million of 1.95% debentures due 2031. The debentures were issued as green bonds, and an amount equal to or in excess of the net proceeds will be disbursed for the construction and development of WPL’s wind and solar EGUs.
IPL [Member] |
Debt [Line Items] |
Debt | DEBT NOTE 7(a) Short-term Debt - In the third quarter of 2021, Alliant Energy, IPL and WPL reallocated credit facility capacity amounts to $500 million for Alliant Energy at the parent company level, $100 million for IPL and $400 million for WPL, within the $1 billion total commitment. Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):
September 30, 2021 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $316 |  | $— |  | $3
Weighted average interest rates | 0.2% |  | N/A |  | 0.1%
Available credit facility capacity | $684 |  | $100 |  | $397
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020
Maximum amount outstanding (based on daily outstanding balances) | $648 |  | $422 |  | $8 |  | $— |  | $320 |  | $139
Average amount outstanding (based on daily outstanding balances) | $560 |  | $252 |  | $— |  | $— |  | $221 |  | $83
Weighted average interest rates | 0.2% |  | 0.2% |  | 0.2% |  | N/A |  | 0.1% |  | 0.2%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $648 |  | $463 |  | $19 |  | $8 |  | $320 |  | $212
Average amount outstanding (based on daily outstanding balances) | $479 |  | $252 |  | $— |  | $— |  | $196 |  | $86
Weighted average interest rates | 0.2% |  | 1.1% |  | 0.2% |  | 0.5% |  | 0.1% |  | 1.2%
NOTE 7(b) Long-term Debt - In September 2021, WPL issued $300 million of 1.95% debentures due 2031. The debentures were issued as green bonds, and an amount equal to or in excess of the net proceeds will be disbursed for the construction and development of WPL’s wind and solar EGUs.
WPL [Member] |
Debt [Line Items] |
Debt | DEBT NOTE 7(a) Short-term Debt - In the third quarter of 2021, Alliant Energy, IPL and WPL reallocated credit facility capacity amounts to $500 million for Alliant Energy at the parent company level, $100 million for IPL and $400 million for WPL, within the $1 billion total commitment. Information regarding Alliant Energy’s, IPL’s and WPL’s commercial paper, and Alliant Energy’s and WPL’s borrowings under the single credit facility, which currently expires in August 2023, classified as short-term debt was as follows (dollars in millions):
September 30, 2021 | Alliant Energy |  | IPL |  | WPL
Amount outstanding | $316 |  | $— |  | $3
Weighted average interest rates | 0.2% |  | N/A |  | 0.1%
Available credit facility capacity | $684 |  | $100 |  | $397
| Alliant Energy |  | IPL |  | WPL
Three Months Ended September 30 | 2021 |  | 2020 |  | 2021 |  | 2020 |  | 2021 |  | 2020
Maximum amount outstanding (based on daily outstanding balances) | $648 |  | $422 |  | $8 |  | $— |  | $320 |  | $139
Average amount outstanding (based on daily outstanding balances) | $560 |  | $252 |  | $— |  | $— |  | $221 |  | $83
Weighted average interest rates | 0.2% |  | 0.2% |  | 0.2% |  | N/A |  | 0.1% |  | 0.2%
Nine Months Ended September 30 |  |  |  |  |  |  |  |  |  |  |
Maximum amount outstanding (based on daily outstanding balances) | $648 |  | $463 |  | $19 |  | $8 |  | $320 |  | $212
Average amount outstanding (based on daily outstanding balances) | $479 |  | $252 |  | $— |  | $— |  | $196 |  | $86
Weighted average interest rates | 0.2% |  | 1.1% |  | 0.2% |  | 0.5% |  | 0.1% |  | 1.2%
NOTE 7(b) Long-term Debt - In September 2021, WPL issued $300 million of 1.95% debentures due 2031. The debentures were issued as green bonds, and an amount equal to or in excess of the net proceeds will be disbursed for the construction and development of WPL’s wind and solar EGUs.

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- Definition The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -URI http://asc.fasb.org/topic&trid=2208564 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1I -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1I -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(c)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1C -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495334-112611 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1E -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495348-112611 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1I -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495371-112611 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 + Details
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