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v3.22.2.2

Debt (Narrative) (Details) - USD ($) $ in Millions | Oct. 31, 2022 | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | --- | ---
Subsequent Event [Member] |  |  |
Debt [Line Items] |  |  |
Line of credit facility, current borrowing capacity | $ 1,000 |  |
Parent Company [Member] | Subsequent Event [Member] |  |  |
Debt [Line Items] |  |  |
Line of credit facility, current borrowing capacity | 500 |  |
IPL [Member] | Subsequent Event [Member] |  |  |
Debt [Line Items] |  |  |
Line of credit facility, current borrowing capacity | 200 |  |
WPL [Member] | Subsequent Event [Member] |  |  |
Debt [Line Items] |  |  |
Line of credit facility, current borrowing capacity | $ 300 |  |
Senior Notes [Member] | 3.6% senior notes, due 2032 [Member] |  |  |
Debt [Line Items] |  |  |
Long-term debt |  | $ 350 |
Interest rate, percent |  | 3.60% |
Senior Notes [Member] | 3.45% senior notes, due 2022 [Member] | Corporate Services [Member] |  |  |
Debt [Line Items] |  |  |
Long-term debt |  |  | $ 75
Interest rate, percent |  |  | 3.45%
Term Loan Credit Agreement [Member] | Term loan credit agreement through March 2024 [Member] |  |  |
Debt [Line Items] |  |  |
Long-term debt |  | $ 300 |
Interest rate, percent |  | 3.00% |
Term Loan Credit Agreement [Member] | Term loan credit agreement through March 2022 [Member] |  |  |
Debt [Line Items] |  |  |
Long-term debt |  |  | $ 300
Debentures [Member] | 3.95% debenture, due 2032 [Member] | WPL [Member] |  |  |
Debt [Line Items] |  |  |
Long-term debt |  | $ 600 |
Interest rate, percent |  | 3.95% |

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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=123466204&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1B -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495323-112611 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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