Income taxes.

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- Definition

Tax rate change of regulatory liability.

+ References

No definition available.

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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- Definition

Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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- Definition

Amount of unrecognized tax benefits.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 740
-SubTopic 10
-Section 45
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- Definition

Amount of increase (decrease) in unrecognized tax benefits attributable to uncertain tax positions taken in tax returns.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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-Paragraph 15A
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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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-Name Accounting Standards Codification
-Topic 740
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Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Income Taxes [Line Items]
Unrecognized tax benefits	$ 5		$ 5		$ 9
Unrecognized tax benefit that would reduce effective tax rate	5		$ 5		$ 9
Federal [Member] \| R&D Tax Credits [Member]
Income Taxes [Line Items]
Unrecognized tax benefits decreased		$ 5
Tampa Electric [Member]
Income Taxes [Line Items]
Effective tax rate			15.40%	16.70%
Florida [Member]
Income Taxes [Line Items]
Federal statutory tax rate			3.53%		4.46%
Regulatory liability	$ 4