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Preferred Stock (Narrative) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Temporary Equity [Line Items] |  |  |
Redemption of IPL's cumulative preferred stock | $ 0 | $ 200 | $ 0
IPL [Member] |  |  |
Temporary Equity [Line Items] |  |  |
Redemption of IPL's cumulative preferred stock | $ 0 | 200 | $ 0
IPL [Member] | Cumulative Preferred Stock [Member] |  |  |
Temporary Equity [Line Items] |  |  |
Shares outstanding (in shares) |  |  | 8,000
Cumulative preferred stock rate |  |  | 5.10%
Preferred stock redemption price per share (in dollars per share) |  |  | $ 25
Redemption of IPL's cumulative preferred stock |  | 200 |
Non-cash charge, preferred stock redemption |  | $ 5 |

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- Definition Amount of preferred stock dividends and adjustments classified as other. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1377-109256 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 7 -Subparagraph (SAB Topic 5.Q) -URI https://asc.fasb.org/extlink&oid=120397183&loc=d3e187283-122770 + Details
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- Definition The cash outflow for reacquisition of callable preferred stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585 + Details
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- Definition The percentage rate used to calculate dividend payments on preferred stock. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644 + Details
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- Definition The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21488-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21475-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI https://asc.fasb.org/extlink&oid=126973232&loc=d3e21564-112644 + Details
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- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. + 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(28)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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