CONDENSED STATEMENTS OF CONSOLIDATED COMPREHENSIVE INCOME (Parentheticals) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Tax benefit (expense) on adjustment related to pension and postretirement plans	$ (1)	$ (1)
Tax expense (benefit) on net deferred gain (loss) from cash flow hedges	0	1
Tax expense (benefit) on reclassification of deferred (gain) loss from cash flow hedges realized in net income	0	0
Houston Electric [Member]
Tax expense (benefit) on net deferred gain (loss) from cash flow hedges	$ 0	$ 1

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan, attributable to parent.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
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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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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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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.

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