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Consolidated Statements of Comprehensive Income - SPC (Parenthetical) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Qualifying hedges, change in fair value, tax | $ (2) | $ (17) | $ (19)
Qualifying hedges, reclassification adjustment, tax | 28 | 27 | 23
Pension and other postretirement benefit plans, gain (loss), tax | 10 | (14) | 18
Reclassification adjustment for amounts included in net income, tax | 0 | 0 | 3
Southern Power |  |  |
Qualifying hedges, change in fair value, tax | (10) | (1) | (30)
Qualifying hedges, reclassification adjustment, tax | 12 | 4 | 26
Pension and other postretirement benefit plans, gain (loss), tax | 2 | (2) | 6
Reclassification adjustment for amounts included in net income, tax | $ 0 | $ 0 | $ 1

X
- Definition Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 12 -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-12 + Details
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X
- Definition Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-12 + Details
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- Definition Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 220 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-12 + Details
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- Definition Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 12 -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482790/220-10-45-12 + Details
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