v3.25.4

CMS Energy Corporation Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Statement of Comprehensive Income [Abstract] |  |  |
Net gain (loss) arising during the period, tax | $ 2 | $ 1 | $ 2
Prior service credit adjustment, tax | 0 | 0 | 0
Amortization of net actuarial loss, tax | 0 | 0 | 0
Amortization of prior service credit, tax | $ 0 | $ 0 | $ 0

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