Regulatory - Additional Information (Detail)												1 Months Ended					12 Months Ended
	Jan. 23, 2023 USD ($)	Sep. 28, 2022 USD ($)	Jul. 01, 2022 USD ($)	Oct. 12, 2021 USD ($)	Aug. 06, 2021 USD ($)	Aug. 03, 2021 USD ($)	Nov. 19, 2020 USD ($)	Aug. 18, 2020 USD ($)	Feb. 07, 2017	Oct. 31, 2013 USD ($)	Sep. 06, 2013	Jan. 31, 2024 USD ($)	Jan. 31, 2023 USD ($)	Nov. 30, 2022 USD ($)	Sep. 30, 2022 USD ($)	Jan. 31, 2022 USD ($)	Dec. 31, 2022 USD ($) Unit $ / kWh MW	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2016	Jun. 09, 2020 USD ($)
Public Utilities General Disclosures [Line Items]
Percentage of ROE																	10.25%
Return on equity range																	range of plus or minus 1%
Allowed equity in the capital structure											54.00%
Base rate adjustment amount			$ 10,000,000
Changes in base rate under agreement																		$ 0
Utility plant, at original costs																	$ 15,474,000,000	14,189,000,000
Accumulated depreciation																	$ 3,845,000,000	3,601,000,000
Number of units applied for recovery | Unit																	3
Adjustment to fuel and capacity charges recovery						$ 83,000,000										$ 169,000,000
Subsequent Event [Member]
Public Utilities General Disclosures [Line Items]
Adjustments to fuel charges recovery	$ 518,000,000
Adjustments to fuel charges recovery projected reduction	$ 170,000,000
Peoples Gas System [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE									10.75%
Allowed equity in the capital structure									54.70%
Utility plant, at original costs																	$ 2,938,000,000
Accumulated depreciation																	(687,000,000)
PGS and OPC [Member]
Public Utilities General Disclosures [Line Items]
Allowed equity in the capital structure							54.70%
Increase in revenue							$ 34,000,000
Impact of tax reform through reduction in base revenue days							120 days
Accumulated depreciation							$ 34,000,000										34,000,000
Date new bottom of return on equity range will remain in effect																					Dec. 31, 2020
Increase in annual base rate							58,000,000
Peoples Gas [Member]
Public Utilities General Disclosures [Line Items]
Accumulated depreciation reversed amount																	14,000,000
Multiple Hurricanes [Member]
Public Utilities General Disclosures [Line Items]
Storm restoration preparation costs																		10,000,000	$ 10,000,000	$ 10,000,000
Hurricane Ian [Member]
Public Utilities General Disclosures [Line Items]
Restoration costs		$ 2,000,000													$ 126,000,000
Storm Reserve Expected to Charge																	119,000,000
Storm restoration costs charged to reserve																	10,000,000
Replenishment of balance in reserve										$ 131,000,000							56,000,000
Regulatory asset for future recovery																	1,000,000
Hurricane Nicole [Member]
Public Utilities General Disclosures [Line Items]
Restoration costs														$ 2,000,000
Intangible Software Assets [Member]
Public Utilities General Disclosures [Line Items]
Accumulated amortization reserve surplus																						$ 16,000,000
Electric Utility Plant [Member]
Public Utilities General Disclosures [Line Items]
Utility plant, at original costs																	$ 12,536,000,000	$ 11,563,000,000
Cast Iron and Bare Steel Replacement Rider [Member] | PGS and OPC [Member]
Public Utilities General Disclosures [Line Items]
Increase in revenue							$ 24,000,000
Settlement Agreement [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement, approval date					Aug. 06, 2021
Allowed equity in the capital structure					54.00%
Base rate adjustment amount					$ 123,000,000
Increase in revenue					$ 191,000,000
Settlement agreement number of subsequent years adjustments					2 years
Basis point increase applicable					0.25%
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] | Subsequent Event [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement adjustment amount													$ 90,000,000
Settlement Agreement [Member] | Scenario Forecast [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement adjustment amount												$ 21,000,000
Settlement Agreement [Member] | US Treasury Bond [Member]
Public Utilities General Disclosures [Line Items]
Calculating period					30 years
Determining period					6 months
Minimum [Member]
Public Utilities General Disclosures [Line Items]
Percentage of ROE			9.25%
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
Decrease bottom return on equity									11.75%
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]
Public Utilities General Disclosures [Line Items]
Percentage of ROE			11.25%
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
Decrease bottom return on equity									9.25%
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]
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%
Solar Project Cost Recovery [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement, extended terms																	four years through 2021
Settlement agreement, approval date																	Nov. 06, 2017
Cost cap of project | $ / kWh																	1,500
Cost savings benefit percentage for projects below cost cap																	75.00%
Solar generation capacity investments																	$ 850,000,000
Solar energy capacity | MW																	600
Estimated revenue requirements																	$ 104,000,000
Investments in gas reserves																	0
Solar Project Cost Recovery [Member] | Solar Base Rate Adjustments [Member]
Public Utilities General Disclosures [Line Items]
True-up amount returned to customers				$ 4,000,000				$ 5,000,000
Solar Project Cost Recovery [Member] | Effective September 2018 [Member]
Public Utilities General Disclosures [Line Items]
Estimated revenue requirements																	24,000,000
Solar Project Cost Recovery [Member] | Effective January 2019 [Member]
Public Utilities General Disclosures [Line Items]
Estimated revenue requirements																	46,000,000
Solar Project Cost Recovery [Member] | Effective January 2020 [Member]
Public Utilities General Disclosures [Line Items]
Estimated revenue requirements																	26,000,000
Solar Project Cost Recovery [Member] | Effective January 2021 [Member]
Public Utilities General Disclosures [Line Items]
Estimated revenue requirements																	$ 8,000,000
Solar Project Cost Recovery [Member] | Minimum [Member]
Public Utilities General Disclosures [Line Items]
Solar project investment term																	2017
Solar Project Cost Recovery [Member] | Maximum [Member]
Public Utilities General Disclosures [Line Items]
Solar project investment term																	2021
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]
Energy generation capacity investments																	$ 876,000,000
AFUDC included in energy project investment																	$ 91,000,000
Accumulated depreciation																			267,000,000
Settlement agreement recovery description																	Tampa Electric’s Settlement Agreement provided recovery for the Big Bend modernization project in two phases. The first phase was 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 Modernization Project [Member] | Electric Utility Plant [Member]
Public Utilities General Disclosures [Line Items]
Utility plant, at original costs																			$ 636,000,000
Big Bend Modernization Project [Member] | Minimum [Member]
Public Utilities General Disclosures [Line Items]
Energy project investment term																	2018
Big Bend Modernization Project [Member] | Maximum [Member]
Public Utilities General Disclosures [Line Items]
Energy project investment term																	2022
Big Bend Coal Generation Assets [Member]
Public Utilities General Disclosures [Line Items]
Settlement agreement cost recovery period																	15 years
Storm Restoration Cost Recovery [Member]
Public Utilities General Disclosures [Line Items]
Minimum cost recovery period																	12 months
Replenishment reserve for recovery of cost										$ 56,000,000