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Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2021 | Mar. 31, 2020
Amortization of net actuarial loss, TAX | $ 0 | $ 0
Unrealized loss on derivative instruments, TAX | 0 | (1)
Consumers Energy Company |  |
Amortization of net actuarial loss, TAX | $ 0 | $ 1

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580 + Details
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