CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - APCo (Parenthetical) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Cash Flow Hedges, Tax	$ (4.1)	$ (12.3)	$ (6.8)	$ (8.0)
Amortization of Pension and OPEB Deferred Costs, Tax	0.1	(0.1)	0.2	(0.3)
APCo
Cash Flow Hedges, Tax	(0.1)	(0.1)	(0.2)	(0.2)
Amortization of Pension and OPEB Deferred Costs, Tax	$ 0.0	$ (0.1)	$ (0.1)	$ (0.2)

Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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

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