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Benefit Plans (Amounts Recognized On The Consolidated Balance Sheets) (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
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Amounts recognized on the balance sheets consist of: |  |
Pension and other benefit obligations | $ (277) | $ (374)
Pension Plans, Defined Benefit [Member] |  |
Amounts recognized on the balance sheets consist of: |  |
Non-current assets | 0 | 0
Current liabilities | (2) | (2)
Pension and other benefit obligations | (167) | (238)
Net amounts recognized at December 31 | (169) | (240)
Amounts recognized in Regulatory Assets consist of: |  |
Net actuarial loss | 376 | 429
Prior service credit | (3) | (4)
Net amount recognized at December 31 | 373 | 425
Other Postretirement Benefits Plans [Member] |  |
Amounts recognized on the balance sheets consist of: |  |
Non-current assets | 9 | 13
Current liabilities | (8) | (8)
Pension and other benefit obligations | (86) | (109)
Net amounts recognized at December 31 | (85) | (104)
Amounts recognized in Regulatory Assets consist of: |  |
Net actuarial loss | 20 | 38
Prior service credit | 0 | (1)
Net amount recognized at December 31 | 20 | 37
IPL [Member] |  |
Amounts recognized on the balance sheets consist of: |  |
Pension and other benefit obligations | (62) | (127)
IPL [Member] | Pension Plans, Defined Benefit [Member] |  |
Amounts recognized on the balance sheets consist of: |  |
Non-current assets | 0 | 0
Current liabilities | 0 | 0
Pension and other benefit obligations | (45) | (105)
Net amounts recognized at December 31 | (45) | (105)
Amounts recognized in Regulatory Assets consist of: |  |
Net actuarial loss | 154 | 180
Prior service credit | (1) | (1)
Net amount recognized at December 31 | 153 | 179
IPL [Member] | Other Postretirement Benefits Plans [Member] |  |
Amounts recognized on the balance sheets consist of: |  |
Non-current assets | 6 | 10
Current liabilities | (2) | (2)
Pension and other benefit obligations | (14) | (18)
Net amounts recognized at December 31 | (10) | (10)
Amounts recognized in Regulatory Assets consist of: |  |
Net actuarial loss | 14 | 13
Prior service credit | 0 | 0
Net amount recognized at December 31 | 14 | 13
WPL [Member] |  |
Amounts recognized on the balance sheets consist of: |  |
Pension and other benefit obligations | (140) | (159)
WPL [Member] | Pension Plans, Defined Benefit [Member] |  |
Amounts recognized on the balance sheets consist of: |  |
Non-current assets | 0 | 0
Current liabilities | 0 | 0
Pension and other benefit obligations | (90) | (96)
Net amounts recognized at December 31 | (90) | (96)
Amounts recognized in Regulatory Assets consist of: |  |
Net actuarial loss | 165 | 188
Prior service credit | 0 | (1)
Net amount recognized at December 31 | 165 | 187
WPL [Member] | Other Postretirement Benefits Plans [Member] |  |
Amounts recognized on the balance sheets consist of: |  |
Non-current assets | 3 | 3
Current liabilities | (5) | (6)
Pension and other benefit obligations | (49) | (61)
Net amounts recognized at December 31 | (51) | (64)
Amounts recognized in Regulatory Assets consist of: |  |
Net actuarial loss | 6 | 18
Prior service credit | 0 | (1)
Net amount recognized at December 31 | $ 6 | $ 17

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