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Consolidated Statements of Comprehensive Income (Unaudited) (Parenthetical) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2021 | Jun. 30, 2020
Amortization of net actuarial loss, TAX | $ 1 | $ 1 | $ 1 | $ 1
Amortization of prior service credit, TAX | 0 | 0 | 0 | 0
Unrealized loss on derivative instruments, TAX | 0 | 0 | 0 | (1)
Reclassification adjustments included in net income , TAX | 1 | 0 | 1 | 0
Consumers Energy Company |  |  |  |
Amortization of net actuarial loss, TAX | $ 0 | $ 0 | $ 0 | $ 1

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- 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 -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e640-108580 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e640-108580 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=124509347&loc=d3e640-108580 + Details
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