Consolidated Statements Of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Amortization of net actuarial loss TAX	$ 0	$ 0
Amortization of prior service credit TAX	0	0
Unrealized loss on investments TAX	0	0
Reclassification adjustments included in net income TAX	0	0
Unrealized loss on derivative instruments TAX	0
Unrealized loss on derivative instruments TAX		0
Consumers Energy Company
Amortization of net actuarial loss TAX	0	0
Unrealized loss on investments TAX	0	0
Reclassification adjustments included in net income TAX	$ 0	$ 0

Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount, after 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

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-SubTopic 10
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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

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Amount of tax expense (benefit), before reclassification adjustments, related to increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities.

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