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Benefit Plans (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Benefit Plans [Line Items] |  |  |
Total plan assets (less than 1%), percentage of common stock | 1.00% | 1.00% |
Common stock percentage in assets held in 401(k) saving plans | 7.00% | 8.00% |
Unrecognized compensation cost | $ 10 |  |
Percentage of base salary and short-term cash incentive compensation | 100.00% |  |
Carrying value of deferred compensation obligations | $ 23 | $ 21 |
Restructuring and voluntary employee separation package pre-tax charge | $ 676 | $ 675 | $ 704
Employee Severance [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Employees accepting voluntary separation package, percent | 5.00% |  |
Restructuring and voluntary employee separation package pre-tax charge | $ 29 |  |
Performance Shares (TSR Metric) [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Performance period | 3 years |  |
Restricted Stock Units [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Performance period | 3 years |  |
Instrument valuation based on shares of common stock, number of shares | 1 |  |
Performance Shares (Net Income and Workforce Composition Metrics) [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Performance period | 3 years |  |
Instrument valuation based on shares of common stock, number of shares | 1 |  |
Minimum [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Unrecognized compensation cost recognized over a weighted average period | 1 year |  |
Minimum [Member] | Performance Shares (TSR Metric) [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Actual number of shares paid out upon vesting, percentage of target shares | 0.00% |  |
Minimum [Member] | Performance Shares (Net Income and Workforce Composition Metrics) [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Actual number of shares paid out upon vesting, percentage of target shares | 0.00% |  |
Maximum [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Unrecognized compensation cost recognized over a weighted average period | 2 years |  |
Maximum [Member] | Performance Shares (TSR Metric) [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Actual number of shares paid out upon vesting, percentage of target shares | 200.00% |  |
Maximum [Member] | Performance Shares (Net Income and Workforce Composition Metrics) [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Actual number of shares paid out upon vesting, percentage of target shares | 200.00% |  |
IPL [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Unrecognized compensation cost | $ 5 |  |
IPL [Member] | Employee Severance [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Restructuring and voluntary employee separation package pre-tax charge | 14 |  |
WPL [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Unrecognized compensation cost | 5 |  |
WPL [Member] | Employee Severance [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Restructuring and voluntary employee separation package pre-tax charge | $ 13 |  |
Omnibus Incentive Plan [Member] |  |  |
Benefit Plans [Line Items] |  |  |
Shares available for issuance under the Amended and Restated OIP (in shares) | 7,000,000 |  |
Shares included in diluted earnings per share (in shares) | 564,743 |  |

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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480429/718-10-50-2 + Details
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