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Leases (Expected Maturities of Operating and Finance Lease Liabilities (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Leases [Line Items] |  |
Operating Leases Liability, 2022 | $ 2 |
Operating Leases Liability, 2023 | 2 |
Operating Leases Liability, 2024 | 2 |
Operating Leases Liability, 2025 | 2 |
Operating Leases Liability, 2026 | 2 |
Operating Leases Liability, Thereafter | 7 |
Operating Leases Liability, Total | 17 |
Operating Leases Liability, Less: amount representing interest | 3 |
Operating Leases Liability, Present value of minimum lease payments | 14 | $ 15
Finance Lease Liability, 2022 | 0 |
Finance Lease Liability, 2023 | 0 |
Finance Lease Liability, 2024 | 0 |
Finance Lease Liability, 2025 | 0 |
Finance Lease Liability, 2026 | 1 |
Finance Lease Liability, Thereafter | 19 |
Finance Lease Liability, Total | 20 |
Finance Lease Liability, Less: amount representing interest | 8 |
Finance Lease Liability, Present value of minimum lease payments | 12 |
IPL [Member] |  |
Leases [Line Items] |  |
Operating Leases Liability, 2022 | 1 |
Operating Leases Liability, 2023 | 1 |
Operating Leases Liability, 2024 | 1 |
Operating Leases Liability, 2025 | 1 |
Operating Leases Liability, 2026 | 1 |
Operating Leases Liability, Thereafter | 6 |
Operating Leases Liability, Total | 11 |
Operating Leases Liability, Less: amount representing interest | 2 |
Operating Leases Liability, Present value of minimum lease payments | 9 | 9
WPL [Member] |  |
Leases [Line Items] |  |
Operating Leases Liability, 2022 | 1 |
Operating Leases Liability, 2023 | 1 |
Operating Leases Liability, 2024 | 1 |
Operating Leases Liability, 2025 | 1 |
Operating Leases Liability, 2026 | 1 |
Operating Leases Liability, Thereafter | 1 |
Operating Leases Liability, Total | 6 |
Operating Leases Liability, Less: amount representing interest | 1 |
Operating Leases Liability, Present value of minimum lease payments | 5 | 6
Finance Lease Liability, 2022 | 15 |
Finance Lease Liability, 2023 | 15 |
Finance Lease Liability, 2024 | 15 |
Finance Lease Liability, 2025 | 6 |
Finance Lease Liability, 2026 | 1 |
Finance Lease Liability, Thereafter | 19 |
Finance Lease Liability, Total | 71 |
Finance Lease Liability, Less: amount representing interest | 18 |
Finance Lease Liability, Present value of minimum lease payments | $ 53 | $ 51

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- Definition Present value of lessee's discounted obligation for lease payments from finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918701-209980 + Details
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