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Debt (Credit Facilities) (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
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Commercial paper and borrowings under the single credit facility: |  |
Amount outstanding | $ 642 | $ 515
Weighted average interest rates | 4.60% | 0.20%
Available credit facility capacity | $ 358 | $ 485
IPL [Member] |  |
Commercial paper and borrowings under the single credit facility: |  |
Amount outstanding | 0 | 0
Available credit facility capacity | 100 | 250
WPL [Member] |  |
Commercial paper and borrowings under the single credit facility: |  |
Amount outstanding | $ 290 | $ 236
Weighted average interest rates | 4.50% | 0.20%
Available credit facility capacity | $ 110 | $ 64

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- Definition Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days. + References Reference 1: 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(13)(2)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 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(a)(16)) -URI https://asc.fasb.org/extlink&oid=126734703&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(19)(a)(3)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Weighted average interest rate of short-term debt outstanding calculated at point in time. + 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)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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