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Leases (Operating Leases) (Details) - USD ($) $ in Millions | Dec. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Leases [Line Items] |  |
Operating leases assets, Property, plant and equipment, net | $ 23 | $ 16
Operating leases liabilities, Other current liabilities | 2 | 3
Operating leases liabilities, Other liabilities | 21 | 13
Operating leases liabilities, Total | $ 23 | $ 16
Operating leases, Weighted average remaining lease term | 12 years | 10 years
Operating leases, Weighted average discount rate, percent | 4.00% | 4.00%
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration] | Property, plant and equipment, net | Property, plant and equipment, net
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] | Other | Other
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List] | Other | Other
IPL [Member] |  |
Leases [Line Items] |  |
Operating leases assets, Property, plant and equipment, net | $ 13 | $ 9
Operating leases liabilities, Other current liabilities | 1 | 1
Operating leases liabilities, Other liabilities | 12 | 8
Operating leases liabilities, Total | $ 13 | $ 9
Operating leases, Weighted average remaining lease term | 12 years | 11 years
Operating leases, Weighted average discount rate, percent | 4.00% | 4.00%
WPL [Member] |  |
Leases [Line Items] |  |
Operating leases assets, Property, plant and equipment, net | $ 9 | $ 6
Operating leases liabilities, Other current liabilities | 1 | 1
Operating leases liabilities, Other liabilities | 8 | 5
Operating leases liabilities, Total | $ 9 | $ 6
Operating leases, Weighted average remaining lease term | 12 years | 9 years
Operating leases, Weighted average discount rate, percent | 4.00% | 4.00%

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