Regulatory - Additional Information (Detail)					1 Months Ended			3 Months Ended	6 Months Ended
	Aug. 01, 2022 BTU	Jul. 01, 2022 USD ($)	Aug. 06, 2021 USD ($)	Nov. 19, 2020 USD ($)	Jan. 31, 2024 USD ($)	Jan. 31, 2023 USD ($)	Jan. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Public Utilities General Disclosures [Line Items]
Changes in base rate under agreement										$ 0
Accumulated depreciation								$ 3,741,000,000	$ 3,741,000,000		$ 3,601,000,000
Additional cost recovery from settlement agreement							$ 169,000,000
Subsequent Event [Member]
Public Utilities General Disclosures [Line Items]
Base rate adjustment amount		$ 10,000,000
PGS and OPC [Member]
Public Utilities General Disclosures [Line Items]
Increase in revenue				$ 34,000,000
Allowed equity in the capital structure				54.70%
Accumulated depreciation				$ 34,000,000				34,000,000	34,000,000
Increase in annual base rate				58,000,000
PGS and OPC [Member] | Cast Iron and Bare Steel Replacement Rider [Member]
Public Utilities General Disclosures [Line Items]
Increase in revenue				$ 24,000,000
PGS [Member]
Public Utilities General Disclosures [Line Items]
Accumulated depreciation reversed amount								$ 5,000,000	$ 10,000,000
Settlement Agreement [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement, approval date			Aug. 06, 2021
Base rate adjustment amount			$ 123,000,000
Increase in revenue			$ 191,000,000
Settlement agreement number of subsequent years adjustments			2 years
Allowed equity in the capital structure			54.00%
Basis point increase applicable			25.00%
Additional attainable revenue under settlement agreement			$ 10,000,000
Changes in base rate under agreement			$ 0
Impact of tax reform through reduction in base revenue days			180 days
Settlement Agreement [Member] | Scenario Forecast [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement adjustment amount					$ 21,000,000	$ 90,000,000
Settlement Agreement [Member] | US Treasury Bond [Member]
Public Utilities General Disclosures [Line Items]
Calculating period			30 years
Determining period			6 months
Minimum [Member] | Subsequent Event [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE		9.25%
PGA change | BTU	1.19163
Minimum [Member] | PGS and OPC [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE				8.90%
Base rate agreement frozen period				Jan. 01, 2021
Minimum [Member] | Settlement Agreement [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE			9.00%
Base rate agreement frozen period			Jan. 01, 2022
Minimum [Member] | Settlement Agreement [Member] | US Treasury Bond [Member]
Public Utilities General Disclosures [Line Items]
ROE revenue basis point on yield rate			0.50%
Maximum [Member] | Subsequent Event [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE		11.25%
PGA change | BTU	1.70492
Maximum [Member] | PGS and OPC [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE				11.00%
Base rate agreement frozen period				Dec. 31, 2023
Maximum [Member] | Settlement Agreement [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE			11.00%
Base rate agreement frozen period			Dec. 31, 2024
Mid Point [Member] | Subsequent Event [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE		10.20%
Mid Point [Member] | PGS and OPC [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE				9.90%
Mid Point [Member] | Settlement Agreement [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE			9.95%
Retiring Assets [Member] | Settlement Agreement [Member]
Public Utilities General Disclosures [Line Items]
Cost recovery from settlement agreement			$ 68,000,000
Retiring Coal Generation Units and Meter Assets [Member] | Settlement Agreement [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement cost recovery period			15 years
Big Bend Modernization Project [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement recovery description									Tampa Electric’s Settlement Agreement provides recovery for the Big Bend modernization project in two phases. The first phase is a revenue increase to cover the costs of the assets in service during 2022, among other items. The remainder of the project costs will be recovered as part of the 2023 subsequent year adjustment.
Big Bend Coal Generation Assets [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement cost recovery period									15 years