Tampa Electric 10-Q 9 Nov 23 2023 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2023	Nov. 08, 2023
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2023
Document Fiscal Year Focus	2023
Document Fiscal Period Focus	Q3
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity Registrant Name	TAMPA ELECTRIC COMPANY
Entity Interactive Data Current	Yes
Entity File Number	1-5007
Entity Address, Address Line One	TECO Plaza
Entity Address, Address Line Two	702 N. Franklin Street
Entity Address, City or Town	Tampa
Entity Address, State or Province	FL
Entity Tax Identification Number	59-0475140
Entity Incorporation, State or Country Code	FL
Entity Address, Postal Zip Code	33602
City Area Code	813
Local Phone Number	228-1111
Document Quarterly Report	true
Document Transition Report	false
Entity Central Index Key	0000096271
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		10

Consolidated Condensed Balance

Consolidated Condensed Balance Sheets (Unaudited) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Property, plant and equipment
Utility plant, at original costs	$ 13,270	$ 15,474
Accumulated depreciation	(3,367)	(3,845)
Utility plant, net	9,903	11,629
Other property	16	15
Total property, plant and equipment, net	9,919	11,644
Current assets
Cash and cash equivalents	8	14
Receivables, less allowance for credit losses of $2 and $4 at September 30, 2023 and December 31, 2022, respectively	372	295
Inventories, at average cost
Regulatory assets	227	361
Prepayments and other current assets	38	35
Total current assets	1,777	909
Other assets
Regulatory assets	889	1,191
Other	53	59
Total other assets	942	1,250
Total assets	12,638	13,803
Capitalization
Common stock	4,505	5,075
Accumulated other comprehensive loss	(1)	(1)
Retained earnings	304	346
Total capital	4,808	5,420
Long-term debt	3,435	3,734
Total capitalization	8,243	9,154
Current liabilities
Long-term debt due within one year	300	0
Notes payable	1,158	1,019
Accounts payable	321	472
Customer deposits	118	145
Regulatory liabilities	86	85
Accrued interest	47	30
Accrued taxes	77	15
Other	40	45
Total current liabilities	2,361	2,037
Long-term liabilities
Deferred income taxes	880	1,045
Regulatory liabilities	727	1,055
Investment tax credits	238	243
Deferred credits and other liabilities	189	269
Total long-term liabilities	2,034	2,612
Commitments and Contingencies (see Note 8)
Total liabilities and capitalization	12,638	13,803
Related Party [Member]
Current assets
Due from affiliates	908	22
Current liabilities
Due to affiliates	214	226
Fuel [Member]
Inventories, at average cost
Utility inventories	48	23
Materials and Supplies [Member]
Inventories, at average cost
Utility inventories	176	159
Electric [Member]
Property, plant and equipment
Utility plant, at original costs	13,270	12,536
Gas [Member]
Property, plant and equipment
Utility plant, at original costs	$ 0	$ 2,938

Consolidated Condensed Balanc_2

Consolidated Condensed Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Allowance for credit losses	$ 2	$ 4

Consolidated Condensed Statemen

Consolidated Condensed Statements of Income and Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenues
Electric	$ 795	$ 752	$ 2,024	$ 1,923
Gas	0	160	0	501
Total revenues	795	912	2,024	2,424
Expenses
Fuel	179	200	455	518
Purchased power	31	69	65	110
Cost of natural gas sold	0	69	0	206
Operations and maintenance	172	159	447	455
Depreciation and amortization	107	110	316	322
Taxes, other than income	67	68	177	195
Total expenses	556	675	1,460	1,806
Income from operations	239	237	564	618
Other income
Allowance for equity funds used during construction	6	8	13	25
Interest income from affiliates	10	0	28	0
Other income, net	8	6	27	12
Total other income	24	14	68	37
Interest charges
Interest expense	60	48	176	126
Interest expense to affiliates	3	0	8	0
Allowance for borrowed funds used during construction	(2)	(4)	(4)	(9)
Total interest charges	61	44	180	117
Income before provision for income taxes	202	207	452	538
Provision for income taxes	32	38	71	106
Net income	170	169	381	432
Comprehensive income	$ 170	$ 169	$ 381	$ 432

Consolidated Condensed Statem_2

Consolidated Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities
Net income	$ 381	$ 432
Adjustments to reconcile net income to cash from operating activities:
Depreciation and amortization	316	322
Deferred income taxes and investment tax credits	(18)	105
Allowance for equity funds used during construction	(13)	(25)
Deferred recovery clauses	312	(327)
Regulatory assets and liabilities	75	(56)
Pension and post-retirement asset and liabilities	(20)	(16)
Other	15	(4)
Increase (Decrease) in Operating Capital [Abstract]
Receivables, less allowance for credit losses	(132)	(104)
Inventories	(47)	(23)
Taxes accrued	81	64
Interest accrued	22	29
Accounts payable	(51)	77
Other	(10)	(10)
Cash flows from operating activities	911	464
Cash flows used in investing activities
Capital expenditures	(889)	(979)
Net proceeds from sale of assets	0	10
Cash flows used in investing activities	(889)	(969)
Cash flows from financing activities
Equity contributions from Parent	300	470
Proceeds from long-term debt issuance	0	595
Repayment of long-term debt	0	(250)
Net increase in short-term debt (maturities of 90 days or less)	139	105
Advances to affiliate	(160)	0
Dividends to Parent	(302)	(348)
Other	(1)	0
Cash flows from (used in) financing activities	(24)	572
Net increase (decrease) in cash and cash equivalents	(2)	67
Cash and cash equivalents at beginning of period (refer to Note 1)	10	18
Cash and cash equivalents at end of period	8	85
Supplemental disclosure of non-cash activities
Change in accrued capital expenditures	(19)	(20)
Change in notes receivable from PGS	$ (736)	$ 0

Consolidated Condensed Statem_3

Consolidated Condensed Statements of Capitalization (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Beginning balance	$ 4,670	$ 5,133	$ 5,420	$ 4,792
Net income	170	169	381	432
Separation of PGS equity from TEC			(992)
Equity contributions from Parent	100	190	300	470
Dividends to Parent	(132)	(146)	(302)	(348)
Other			1
Ending balance	4,808	5,346	4,808	5,346
Common Stock [Member]
Beginning balance	$ 4,405	$ 4,750	$ 5,075	$ 4,470
Beginning balance	10	10	10	10
Separation of PGS equity from TEC			$ (871)
Equity contributions from Parent	$ 100	$ 190	300	$ 470
Other			1
Ending balance	$ 4,505	$ 4,940	$ 4,505	$ 4,940
Ending balance	10	10	10	10
Retained Earnings [Member]
Beginning balance	$ 266	$ 384	$ 346	$ 323
Net income	170	169	381	432
Separation of PGS equity from TEC			(121)
Dividends to Parent	(132)	(146)	(302)	(348)
Ending balance	304	407	304	407
Accumulated Other Comprehensive Loss [Member]
Beginning balance	(1)	(1)	(1)	(1)
Ending balance	$ (1)	$ (1)	$ (1)	$ (1)

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	1. Summary of Significant Accounting Policies See TEC’s Annual Report on Form 10-K for the year ended December 31, 2022 for a complete discussion of accounting policies. The significant accounting policies for TEC include: Principles of Consolidation and Basis of Presentation TEC is a wholly owned subsidiary of TECO Energy, which is an indirect, wholly owned subsidiary of Emera. TEC is comprised of the electric division, referred to as Tampa Electric, and prior to January 1, 2023, the natural gas division, referred to as PGS. See "Separation of PGS from TEC" below for further information. In the opinion of management, the unaudited consolidated condensed financial statements include all adjustments that are of a recurring nature and necessary to state fairly the financial position of TEC as of September 30, 2023 and December 31, 2022, and the results of operations and cash flows for the periods ended September 30, 2023 and 2022. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results that can be expected for the entire fiscal year ending December 31, 2023. The use of estimates is inherent in the preparation of financial statements in accordance with U.S. GAAP. Actual results could differ from these estimates. The year-end Consolidated Condensed Balance Sheet was derived from audited financial statements; however, this quarterly report on Form 10-Q does not include all year-end disclosures required for an annual report on Form 10-K by U.S. GAAP. Separation of PGS from TEC PGS became an operating division of TEC in 1997 when TECO Energy purchased PGS and merged that corporation into TEC. Since then, PGS has operated as a stand-alone regulated utility, including having its own tariffs and its own books and records. On January 1, 2023, TEC transferred the assets and liabilities of its PGS division into a separate corporation called Peoples Gas System, Inc. pursuant to a Contribution Agreement. This new corporation is a wholly owned subsidiary of a newly formed gas operations holding company, TECO Gas Operations, Inc., a wholly owned subsidiary of TECO Energy. On January 1, 2023, the assets, liabilities, and equity that had been recorded in the books of PGS were transferred from TEC to the newly formed company at book value in a tax-free transaction. PGS issued 100 shares of common stock to TEC related to the transfer, which were subsequently distributed to TECO Energy, Inc. and then contributed to TECO Gas Operations, Inc. As a result, from and after January 1, 2023, the PGS division is no longer operated by TEC. This is a transaction between entities under common control; therefore, TEC did no t recognize a gain or loss on the transaction. TEC is not required to recast its prior period financial statements and disclosures to exclude PGS prior to January 1, 2023. The TEC consolidated condensed statement of cash flows for the nine months ended September 30, 2023 does not include the non-cash impact of separating the PGS assets, liabilities and equity from TEC on January 1, 2023 and excludes PGS’s opening cash balance. The impact of the separation of PGS from TEC on the consolidated condensed statements of capital for the nine months ended September 30, 2023 was $ 992 million, which represents the net assets of PGS transferred as of January 1, 2023. TEC recorded $ 121 million to retained earnings, which was the retained earnings of PGS as of January 1, 2023, and the remainder of $ 871 million was recorded to additional paid in capital, which is presented with common stock. Included in the liabilities transferred was PGS’s allocation of outstanding unsecured notes and outstanding short-term borrowings issued by TEC. The obligations related to these combined borrowings are reflected in a loan agreement between TEC and PGS. The initial obligation of PGS under the loan agreement at January 1, 2023 was a term loan in the principal amount of $ 670 million and a revolving loan in the principal amount of $ 66 million. The maturity date for both is December 29, 2023. PGS intends to access the third-party lending market during 2023 but cannot predict when during the year that it will do so. To assist its affiliate and to facilitate an orderly transfer of its gas assets, Tampa Electric will continue to be responsible for providing capital as needed to PGS under a loan agreement. See Note 12 for further information regarding TEC's related party transactions with PGS. For the stand alone PGS balance sheet as of December 31, 2022, see Note 1 of TEC’s Annual Report on Form 10-K for the year ended December 31, 2022. Receivables and Allowance for Credit Losses Receivables on the Consolidated Condensed Balance Sheets include receivables from contracts with customers, which consist of services to residential, commercial, industrial and other customers, totaling $ 362 million and $ 295 million as of September 30, 2023 and December 31, 2022, respectively. An allowance for credit losses is established based on TEC’s collection experience and reasonable and supportable forecasts that affect the collectibility of the reported amount. Circumstances that could affect TEC’s estimates of credit losses include, but are not limited to, customer credit issues, generating fuel prices, customer deposits and general economic conditions. Accounts are reserved in the allowance or written off once they are deemed to be uncollectible. As of September 30, 2023 and December 31, 2022, unbilled revenues of $ 81 million and $ 82 million, respectively, are included in the “Receivables” line item on the Consolidated Condensed Balance Sheets. Accounting for Franchise Fees and Gross Receipts TEC is allowed to recover certain costs from customers on a dollar-for-dollar basis through rates approved by the FPSC. The amounts included in customers’ bills for franchise fees and gross receipt taxes are included as revenues on the Consolidated Condensed Statements of Income. Franchise fees and gross receipt taxes payable by TEC are included as an expense on the Consolidated Condensed Statements of Income in “Taxes, other than income”. These amounts totaled $ 43 million and $ 41 million for the three months ended September 30, 2023 and 2022, respectively, and totaled $ 106 million and $ 110 million for the nine months ended September 30, 2023 and 2022, respectively.

New Accounting Pronouncements

New Accounting Pronouncements	9 Months Ended
	Sep. 30, 2023
Accounting Changes and Error Corrections [Abstract]
New Accounting Pronouncements	2. New Accounting Pronouncements TEC considers the applicability and impact of all ASUs issued by the FASB. The ASUs that have been issued, but that are not yet effective, were assessed and determined to be either not applicable to TEC or have an insignificant impact on the consolidated condensed financial statements.

Regulatory

Regulatory	9 Months Ended
	Sep. 30, 2023
Regulated Operations [Abstract]
Regulatory	3. Regulatory Tampa Electric Base Rates On August 6, 2021, Tampa Electric filed with the FPSC a joint motion for approval of a settlement agreement dated as of August 6, 2021 (the Settlement Agreement) by and among Tampa Electric and the intervenors in Tampa Electric’s rate case filed with the FPSC in April 2021. The Settlement Agreement agreed to an increase in base rates annually effective with January 2022 bills, to generate a $ 191 million increase in revenue consisting of $ 123 million of traditional base rate charges and $ 68 million in a new charge to recover the costs of retiring assets. The Settlement Agreement further included two subsequent year adjustments of $ 90 million and $ 21 million, effective January 2023 and January 2024, respectively. Under the agreement, the allowed equity in the capital structure continued to be 54 % from investor sources of capital. The Settlement Agreement included an allowed regulatory ROE range of 9.0 % to 11.0 % with a 9.95 % midpoint. The Settlement Agreement allows a 25 basis point increase in the allowed ROE range and mid-point, and $ 10 million of additional revenue, if the average 30-year United States Treasury Bond yield rate for any period of six consecutive months is at least 50 basis points greater than the yield rate on the date the FPSC votes to approve the agreement. Under the agreement, base rates will no t change from January 1, 2022 through December 31, 2024 , unless Tampa Electric’s earned ROE were to fall below the bottom of the range during that time. The Settlement Agreement contained a provision whereby Tampa Electric agreed to quantify the future impact of a decrease or increase in corporate income tax rates on net operating income through a reduction or increase in base revenues within 180 days of when such tax change becomes law or its effective date. The Settlement Agreement further created a mechanism to recover the costs of retiring coal generation units and meter assets over a period of 15 years which survives the term of that agreement. The Settlement Agreement set new depreciation and dismantlement rates effective January 1, 2022 and contained the provisions that Tampa Electric will not have to file another depreciation study during the term of the agreement but will file a new depreciation study no more than one year, nor less than 90 days, before the filing of its next general base rate proceeding. Additionally, Tampa Electric agreed to a financial hedging moratorium for natural gas ending on December 31, 2024. On October 21, 2021, the FPSC approved the Settlement Agreement and the final order, reflecting such approval, was issued on November 10, 2021. Tampa Electric ROE Adjustment Pursuant to the Settlement Agreement, on July 1, 2022, Tampa Electric requested to adjust its base rates to collect an additional $ 10 million annually (prorated in the first year) effective September 1, 2022 and increase its mid-point ROE and upper and lower allowed ranges. On August 16, 2022, the FPSC approved the change. The new mid-point ROE is 10.20 %, and the range is 9.25 % to 11.25 % effective July 1, 2022. Tampa Electric Mid-Course Adjustment to Fuel Recovery In January 2022, Tampa Electric requested a mid-course adjustment to its fuel and capacity charges to recover an additional $ 169 million beginning April 1, 2022 through December 2022 due to an increase in fuel commodity and capacity costs. On March 1, 2022, the FPSC voted to approve the mid-course adjustment, and the order reflecting such approval was issued on March 18, 2022. On January 23, 2023, Tampa Electric requested an adjustment to its fuel charges to recover the $ 518 million final 2022 fuel under-recovery over a period of 21 months. The request also included an adjustment to 2023 projected fuel costs to reflect the reduction in natural gas prices since September 2022 for a projected reduction of $ 170 million for the balance of 2023. The changes were approved by the FPSC on March 7, 2023, effective April 1, 2023. Tampa Electric Storm Restoration Cost Recovery As a result of Tampa Electric’s 2013 rate case settlement, in the event of a named storm that results in damage to its system, Tampa Electric can petition the FPSC to seek recovery of those costs over a 12-month period or longer as determined by the FPSC, as well as replenish its reserve to $ 56 million, the level of the reserve as of October 31, 2013. Once the storm reserve regulatory liability is exhausted, TEC may petition the FPSC for recovery. This provision was also included in Tampa Electric’s subsequent 2017 amended and restated settlement agreement and in Tampa Electric’s 2021 rate case settlement agreement. In 2021, 2020 and 2019, Tampa Electric incurred total storm restoration costs for multiple hurricanes of approximately $ 10 million, which was charged to the storm reserve regulatory liability. In September 2022, Tampa Electric was impacted by Hurricane Ian. Total restoration costs were $ 129 million, with $ 121 million charged to the storm reserve. Restoration costs charged to the storm reserve exceeded the reserve balance and this amount was deferred to be collected from customers in subsequent periods. In November 2022, Tampa Electric incurred costs of approximately $ 2 million related to Hurricane Nicole. In January 2023, Tampa Electric petitioned the FPSC for recovery of costs associated with Hurricanes Ian and Nicole that exceeded the reserve, $ 10 million of storm restoration costs charged to the reserve since 2018, and the replenishment of the balance in the reserve to the $ 56 million level that existed as of October 31, 2013 for a total of approximately $ 131 million. The storm cost recovery surcharge was approved by the FPSC on March 7, 2023, and Tampa Electric began applying the surcharge on April 2023 bills. Subsequently, on November 9, 2023, the FPSC approved Tampa Electric’s petition filed on August 16, 2023 to update the total storm cost collection to approximately $ 134 million and change the collection of the expected remaining balance of approximately $ 29 million as of December 31, 2023, from over the first three months of 2024 to over the 12 months of 2024. The storm recovery is subject to review of the underlying costs for prudency by the FPSC and issuance of an order by the FPSC is expected to occur by the third quarter of 2024. In September 2023, Tampa Electric was impacted by Hurricane Idalia. The related storm restoration costs were $ 36 million, which were charged to the storm reserve regulatory asset and not included in the petition above. Tampa Electric will determine the timing of the request for recovery of Hurricane Idalia costs at a future time. Tampa Electric Storm Protection Cost Recovery Clause and Settlement Agreement On October 3, 2019, the FPSC issued a rule to implement a Storm Protection Plan (SPP) Cost Recovery Clause. This clause provides a process for Florida investor-owned utilities, including Tampa Electric, to recover transmission and distribution storm hardening costs for incremental activities not already included in base rates. A settlement agreement was approved on August 10, 2020 and Tampa Electric’s cost recovery began in January 2021. The current approved plan addresses the years 2023, 2024 and 2025 and was approved by the FPSC on October 4, 2022. Regulatory Assets and Liabilities Details of the regulatory assets and liabilities are presented in the following table: Regulatory Assets and Liabilities (millions) September 30, 2023 December 31, 2022 Regulatory assets: Regulatory tax asset (1) $ 111 $ 124 Cost-recovery clauses (2) 199 525 Capital cost recovery for early retired assets (3) 499 497 Environmental remediation (4) 0 20 Postretirement benefits (5) 238 272 Asset retirement obligation (6) 11 13 Storm reserve (7) 39 76 Other 19 25 Total regulatory assets 1,116 1,552 Less: Current portion 227 361 Long-term regulatory assets $ 889 $ 1,191 Regulatory liabilities: Regulatory tax liability (8) $ 478 $ 601 Cost-recovery clauses - deferred balances (2) 23 30 Accumulated reserve - cost of removal (9) 288 498 Other 24 11 Total regulatory liabilities 813 1,140 Less: Current portion 86 85 Long-term regulatory liabilities $ 727 $ 1,055 (1) The regulatory tax asset is primarily associated with the depreciation and recovery of AFUDC-equity. This asset does not earn a return but rather is included in the capital structure, which is used in the calculation of the weighted cost of capital used to determine revenue requirements. It will be recovered over the expected life of the related assets. (2) These assets and liabilities are related to FPSC clauses and riders, primarily related to the fuel clause and the increase in natural gas prices experienced in 2022. They are recovered or refunded through cost-recovery mechanisms approved by the FPSC on a dollar-for-dollar basis in a subsequent period. (3) This asset is related to the remaining net book value of Big Bend Units 1 through 3 and meter assets that were retired. The balance earns a rate of return as permitted by the FPSC and will be recovered as a separate line item on customer bills for a period of 15 years . See “Tampa Electric Base Rates” above for further information. (4) This asset was related to PGS costs associated with environmental remediation primarily at MGP sites. (5) This asset is related to the deferred costs of postretirement benefits and it is amortized over the remaining service life of plan participants. Deferred costs of postretirement benefits that are included in expense are recognized as cost of service for rate-making purposes as permitted by the FPSC. (6) This asset is related to costs associated with an asset retirement obligation, which is a legal obligation for the future retirement of certain tangible, long-lived assets. This regulatory asset does not earn a return because it is offset with related assets and liabilities within rate base. It is recovered and removed as the obligation is settled and removed as the activities for the retirement of the related assets have been completed. (7) See "Tampa Electric Storm Restoration Cost Recovery" above for information regarding this reserve. The regulatory asset is included in rate base and earns interest as permitted by the FPSC. (8) The regulatory tax liability is primarily related to the revaluation of TEC’s deferred income tax balances recorded on December 31, 2017 at the lower corporate income tax rate due to U.S. tax reform. The liability related to the revaluation of the deferred income tax balances is amortized and returned to customers through rate reductions or other revenue offsets based on IRS regulations and the settlement agreement for tax reform benefits approved by the FPSC. (9) This item represents the non-ARO cost of removal in the accumulated reserve for depreciation. AROs are costs for legally required removal of property, plant and equipment. Non-ARO cost of removal represents estimated funds received from customers through depreciation rates to cover future non-legally required cost of removal of property, plant and equipment, net of salvage value upon retirement, which reduces rate base for ratemaking purposes. This liability is reduced as costs of removal are incurred.

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2023
Income Tax Disclosure [Abstract]
Income Taxes	4. Income Taxes Inflation Reduction Act On August 16, 2022, the Inflation Reduction Act was signed into legislation and includes numerous tax incentives for clean energy, such as the extension and modification of existing investment and production tax credits for projects placed in service through 2024, and introduces new technology-neutral clean energy related credits beginning in 2025. TEC has determined that electing production tax credits for its solar plants placed in service in 2022 will be more beneficial for customers compared to ITCs and has recorded a $ 20 million regulatory liability in recognition of its obligation to pass the tax benefits to customers as of September 30, 2023. Income Tax Expense TEC is included in a consolidated U.S. federal income tax return with EUSHI and its subsidiaries. TEC’s income tax expense is based upon a separate return method, modified for the benefits-for-loss allocation in accordance with respective tax sharing agreements with TECO Energy and EUSHI. To the extent that TEC’s cash tax positions are settled differently than the amount reported as realized under the tax sharing agreement, the difference is accounted for as either a capital contribution or a distribution. TEC’s effective tax rates for the nine months ended September 30, 2023 and 2022 were 15.7 % and 19.7 %, respectively. The September 30, 2023 and 2022 effective tax rates are an estimate of the annual effective income tax rate. TEC’s effective tax rate for the nine months ended September 30, 2023 differed from the statutory rate principally due to production tax credits and amortization of the regulatory tax liability resulting from tax reform. TEC’s effective tax rate for the nine months ended September 30, 2022 differed from the statutory rate principally due to the amortization of the regulatory tax liability resulting from tax reform. The effective tax rate for the nine months ended September 30, 2023 is lower compared to the same period in 2022 primarily due to production tax credits and the PGS separation from TEC on January 1, 2023. See Note 1 for further information regarding the PGS separation from TEC and Note 3 for further information regarding the regulatory tax liability. Unrecognized Tax Benefits As of September 30, 2023 and December 31, 2022, the amount of unrecognized tax benefits was $ 9 million, all of which was recorded as a reduction of deferred income tax assets for tax credit carryforwards. The unrecognized tax benefits, if recognized, would reduce TEC’s effective tax rate.

Employee Postretirement Benefit

Employee Postretirement Benefits	9 Months Ended
	Sep. 30, 2023
Retirement Benefits [Abstract]
Employee Postretirement Benefits	5. Employee Postretirement Benefits TEC is a participant in the comprehensive retirement plans of TECO Energy. The following table presents detail related to TECO Energy’s periodic benefit cost for pension and other postretirement benefits. Amounts disclosed for TECO Energy’s pension benefits include the amounts related to its qualified pension plan and non-qualified, non-contributory SERP and Restoration Plan. TECO Energy Benefit Cost (millions) Pension Benefits Other Postretirement Benefits Three months ended September 30, 2023 2022 2023 2022 Components of net periodic benefit cost Service cost $ 3 $ 5 $ 0 $ 0 Interest cost 8 6 2 1 Expected return on assets ( 13 ) ( 13 ) 0 0 Amortization of: Actuarial loss (gain) 2 4 0 1 Net periodic benefit cost $ 0 $ 2 $ 2 $ 2 Nine months ended September 30, Components of net periodic benefit cost Service cost $ 11 $ 14 $ 0 $ 1 Interest cost 26 18 6 4 Expected return on assets ( 40 ) ( 39 ) 0 0 Amortization of: Actuarial loss (gain) 4 13 ( 1 ) 1 Settlement cost (1) 2 1 0 0 Net periodic benefit cost $ 3 $ 7 $ 5 $ 6 (1) Represents TEC's SERP and Restoration Plan settlement charges as a result of the prior retirements of certain executives. TEC’s portion of the net periodic benefit cost for the three months ended September 30, 2023 and 2022, respectively, was $ 0 and $ 1 million for pension benefits, and $ 1 million and $ 2 million for other postretirement benefits. TEC’s portion of the net periodic benefit cost for the nine months ended September 30, 2023 and 2022, respectively, was $ 1 million and $ 5 million for pension benefits, and $ 4 million and $ 7 million for other postretirement benefits. TEC’s portion of net periodic benefit costs for pension and other benefits is included as an expense on the Consolidated Condensed Statements of Income in “Operations & maintenance”. TECO Energy assumed a long-term EROA of 7.05 % and a discount rate of 5.55 % for pension benefits under its qualified pension plan for 2023. For TECO Energy’s other postretirement benefits, TECO Energy used a discount rate of 5.53 % for 2023. TECO Energy made contributions of $ 16 million and $ 19 million to its qualified pension plan in the nine months ended September 30, 2023 and 2022, respectively. TEC’s portion of these contributions was $ 10 million and $ 15 million, respectively. TECO Energy does not expect to make additional contributions to the pension plan for the remainder of 2023. Included in the benefit cost discussed above, for the three and nine months ended September 30, 2023, $ 0 and $ 1 million, respectively, of unamortized prior service benefits and costs and actuarial gains and losses were reclassified by TEC from regulatory assets to the Consolidated Condensed Statement of Income, compared with $ 5 million and $ 14 million for the three and nine months ended September 30, 2022, respectively.

Short-Term Debt

Short-Term Debt	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Short-Term Debt	6. Short-Term Debt Details of TEC’s short-term borrowings are presented in the following table: September 30, 2023 December 31, 2022 Borrowings Borrowings Letters Borrowings Borrowings Letters Credit Outstanding - Outstanding - of Credit Credit Outstanding - Outstanding - of Credit (millions) Facilities Credit Facilities (1) Commercial Paper (1) Outstanding Facilities Credit Facilities (1) Commercial Paper (1) Outstanding 5-year facility (2) $ 800 $ 0 $ 758 $ 1 $ 800 $ 0 $ 619 $ 1 1-year term facility (3) 400 400 0 0 400 400 0 0 1-year term facility (4) 200 0 0 0 0 0 0 0 1-year term facility (5) 200 0 0 0 0 0 0 0 Total $ 1,600 $ 400 $ 758 $ 1 $ 1,200 $ 400 $ 619 $ 1 (1) Borrowings outstanding are reported as notes payable. (2) This 5-year facility matures on December 17, 2026 . TEC also has an active commercial paper program for up to $ 800 million, of which the full amount outstanding is backed by TEC’s credit facility. The amount of commercial paper issued results in an equal amount of its credit facility being considered drawn and unavailable. (3) This 1-year term facility was set to mature on December 16, 2022 . On December 13, 2022, TEC extended the maturity date to December 13, 2023. (4) On March 1, 2023, TEC entered into a 1-year term facility that matures on February 28, 2024 . (5) On April 3, 2023, TEC entered into a 1-year term facility that matures on April 1, 2024 . At September 30, 2023, these credit facilities required a commitment fee of 12.5 basis points. The weighted-average interest rate on borrowings outstanding under the credit facilities and commercial paper at September 30, 2023 and December 31, 2022 was 5.85 % and 5.00 %, respectively. TEC Term Loans On March 1, 2023, TEC entered into a 364-day, $ 200 million senior unsecured revolving loan credit facility with a maturity date of February 28, 2024 . The credit agreement contains customary representations and warranties, events of default, and financial and other covenants; and provides for interest to accrue at variable rates based on either the term secured overnight financing rate (SOFR), The Bank of Nova Scotia’s prime rate, the federal funds rate or the one-month secured overnight financing rate, plus a margin. On April 3, 2023, TEC entered into an additional 364-day, $ 200 million senior unsecured revolving loan credit facility with a group of banks. The credit facility has a maturity date of April 1, 2024 . The credit agreement contains customary representations and warranties, events of default, and financial and other covenants; and provides for interest to accrue at variable rates based on either the term SOFR, Wells Fargo’s prime rate, the federal funds rate or the one-month secured overnight financing rate, plus a margin.

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Long-Term Debt	7. Long-Term Debt Fair Value of Long-Term Debt At September 30, 2023, TEC’s long-term debt, including the current portion, had a carrying amount of $ 3,735 million and an estimated fair market value of $ 3,046 million. At December 31, 2022, long-term debt had a carrying amount of $ 3,734 million and an estimated fair market value of $ 3,234 million. The fair value of the debt securities is determined using Level 2 measurements (see Note 11 for information regarding the fair value hierarchy).

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	8. Commitments and Contingencies Legal Contingencies From time to time, TEC and its subsidiaries are involved in various legal, tax and regulatory proceedings before various courts, regulatory commissions and governmental agencies in the ordinary course of business. Where appropriate, accruals are made in accordance with accounting standards for contingencies to provide for matters that are probable of resulting in an estimable loss. Superfund and Former Manufactured Gas Plant Sites As of December 31, 2022, TEC, through its Tampa Electric division and former PGS division, was a PRP for certain superfund sites and, through its former PGS division, for certain former MGP sites. As a result of the separation of the PGS division, PGS is now the responsible party for those sites (in addition to third party PRPs for certain sites). See Note 1 for further information regarding the PGS separation from TEC. Long-Term Commitments TEC has commitments for various purchases as disclosed below, including payment obligations under contractual agreements for fuel, fuel transportation and power purchases that are recovered from customers under regulatory clauses. The following is a schedule of future payments under PPAs, minimum lease payments with non-cancelable lease terms in excess of one year, and other net purchase obligations/commitments at September 30, 2023: Fuel Long-term Demand Purchased Capital and Service Operating Side (millions) Power Transportation Projects Gas Supply (1) Agreements Leases Management Total 2023 $ 4 $ 31 $ 460 $ 94 $ 8 $ 1 $ 1 $ 599 2024 0 132 163 201 34 3 5 538 2025 0 128 18 69 22 2 4 243 2026 0 125 4 18 23 1 1 172 2027 0 125 1 4 22 1 1 154 Thereafter 0 930 0 1 50 46 0 1,027 Total future minimum payments $ 4 $ 1,471 $ 646 $ 387 $ 159 $ 54 $ 12 $ 2,733 (1) As of September 30, 2023, $ 3 million of fuel and gas supply contractual obligations were held between Tampa Electric and Emera Energy Services, a related party. Debt Covenants TEC must meet certain financial tests, including a debt to capital ratio, as defined in the applicable debt agreements and has certain restrictive covenants in specific agreements and debt instruments. At September 30, 2023, TEC was in compliance with all required covenants.

Segment Information

Segment Information	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Segment Information	9. Segment Information Due to the separation of PGS from TEC, TEC operates under a single operating and reportable segment effective January 1, 2023 because the operations of TEC only include the operations of the Electric division. See "Separation of PGS from TEC" in Note 1 for further information regarding the separation of PGS from TEC. (millions) Tampa Eliminations/ Tampa Electric Three months ended September 30, Electric PGS Reclassifications Company 2023 Revenues - external $ 795 $ 795 Intracompany sales 0 0 Total revenues 795 795 Total interest charges 61 61 Net income $ 170 $ 170 2022 Revenues - external $ 752 $ 160 $ 0 $ 912 Intracompany sales 1 1 ( 2 ) 0 Total revenues 753 161 ( 2 ) 912 Total interest charges 37 7 0 44 Net income $ 153 $ 16 $ 0 $ 169 Nine months ended September 30, 2023 Revenues - external $ 2,024 $ 2,024 Intracompany sales 0 0 Total revenues 2,024 2,024 Total interest charges 180 180 Net income $ 381 $ 381 2022 Revenues - external $ 1,923 $ 501 $ 0 $ 2,424 Intracompany sales 3 3 ( 6 ) 0 Total revenues 1,926 504 ( 6 ) 2,424 Total interest charges 99 18 0 117 Net income $ 367 $ 65 $ 0 $ 432 Total assets at September 30, 2023 $ 13,286 $ ( 648 ) (1) $ 12,638 Total assets at December 31, 2022 $ 12,064 $ 2,471 (2) $ ( 732 ) (1) $ 13,803 (1) Amounts primarily relate to consolidated deferred tax reclassifications. Deferred tax assets are reclassified and netted with deferred tax liabilities upon consolidation. (2) For the summary of the assets and liabilities of PGS as of December 31, 2022, see Note 1 of TEC’s Annual Report on Form 10-K for the year ended December 31, 2022.

Revenue

Revenue	9 Months Ended
	Sep. 30, 2023
Revenues [Abstract]
Revenue	10. Revenue The following disaggregates TEC’s revenue by major source: (millions) Tampa Tampa Electric Three months ended September 30, 2023 Electric PGS Eliminations Company Electric revenue Residential $ 567 $ 567 Commercial 234 234 Industrial 56 56 Regulatory deferrals ( 137 ) ( 137 ) Unbilled revenue ( 8 ) ( 8 ) Other (1) 83 83 Total electric revenue 795 795 Total revenue $ 795 $ 795 Three months ended September 30, 2022 Electric revenue Residential $ 445 $ 0 $ 0 $ 445 Commercial 194 0 0 194 Industrial 45 0 0 45 Regulatory deferrals ( 11 ) 0 0 ( 11 ) Unbilled revenue ( 12 ) 0 0 ( 12 ) Other (1) 92 ` 0 ( 1 ) 91 Total electric revenue 753 0 ( 1 ) 752 Gas revenue Residential 0 47 0 47 Commercial 0 46 0 46 Industrial (2) 0 7 0 7 Other (3) 0 61 ( 1 ) 60 Total gas revenue 0 161 ( 1 ) 160 Total revenue $ 753 $ 161 $ ( 2 ) $ 912 (millions) Tampa Tampa Electric Nine months ended September 30, 2023 Electric PGS Eliminations Company Electric revenue Residential $ 1,322 $ 1,322 Commercial 605 605 Industrial 152 152 Regulatory deferrals ( 297 ) ( 297 ) Unbilled revenue 16 16 Other (1) 226 226 Total electric revenue 2,024 2,024 Total revenue $ 2,024 $ 2,024 Nine months ended September 30, 2022 Electric revenue Residential $ 1,063 $ 0 $ 0 $ 1,063 Commercial 501 0 0 501 Industrial 129 0 0 129 Regulatory deferrals ( 17 ) 0 0 ( 17 ) Unbilled revenue 13 0 0 13 Other (1) 237 0 ( 3 ) 234 Total electric revenue 1,926 0 ( 3 ) 1,923 Gas revenue Residential 0 172 0 172 Commercial 0 151 0 151 Industrial (2) 0 22 0 22 Other (3) 0 159 ( 3 ) 156 Total gas revenue 0 504 ( 3 ) 501 Total revenue $ 1,926 $ 504 $ ( 6 ) $ 2,424 (1) Other electric revenue includes sales to public authorities, off-system sales to other utilities and various other items. (2) Industrial gas revenue includes sales to power generation customers. (3) Other gas revenue includes off-system sales to other utilities and various other items. Remaining Performance Obligations Remaining performance obligations primarily represent lighting contracts and gas transportation contracts with fixed contract terms. As of September 30, 2023 and December 31, 2022, the aggregate amount of the transaction price allocated to remaining performance obligations was approximately $ 62 million and $ 140 million, respectively. The decrease is due to TEC's January 1, 2023 separation from its former PGS division. See Note 1 for further information regarding the separation of PGS from TEC. As allowed under ASC 606, these amounts exclude contracts with an original expected length of one year or less and variable amounts for which TEC recognizes revenue at the amount to which it has the right to invoice for services performed. TEC expects to recognize revenue for the remaining performance obligations through 2043 .

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2023
Fair Value Disclosures [Abstract]
Fair Value Measurements	11. Fair Value Measurements Items Measured at Fair Value on a Recurring Basis Accounting guidance governing fair value measurements and disclosures provides that fair value represents the amount that would be received in selling an asset or the amount that would be paid in transferring a liability in an orderly transaction between market participants. As a basis for considering assumptions that market participants would use in pricing an asset or liability, accounting guidance also establishes a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: Level 1: Observable inputs, such as quoted prices in active markets; Level 2: Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and Level 3: Unobservable inputs for which there is little or no market data, which require the reporting entity to develop its own assumptions. There were no Level 3 assets or liabilities for the periods presented. As of September 30, 2023 and December 31, 2022, the carrying value of TEC’s short-term debt was not materially different from the fair value due to the short-term nature of the instruments and because the stated rates approximate market rates. The fair value of TEC’s short-term debt is determined using Level 2 measurements. See Note 7 for information regarding the fair value of long-term debt.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2023
Related Party Transactions [Abstract]
Related Party Transactions	12. Related Party Transactions A summary of activities between TEC and its affiliates follows: Net transactions with affiliates Three months ended September 30, Nine months ended September 30, (millions) 2023 2022 2023 2022 Natural gas purchases (net of sales) from affiliates $ 21 $ 71 $ 57 $ 185 Services to/(from) affiliates 8 ( 1 ) 23 ( 4 ) Interest income from affiliates 10 0 28 0 Interest expense to affiliates 3 0 8 0 Equity contributions from TECO Energy 100 190 300 470 Dividends to TECO Energy 132 146 302 348 Amounts due from or to affiliates (millions) September 30, 2023 December 31, 2022 Note receivable from PGS (1) $ 889 $ 0 Interest receivable from PGS (1) 4 0 Accounts receivable related to asset management agreements to Emera Energy Services Inc. (2) 4 7 Accounts receivable excluding asset management agreements (2) 11 5 Taxes receivable (3) 0 10 Accounts payable (2) 14 31 Note payable to TECO Energy (4) 195 195 Interest payable to TECO Energy (4) 1 0 Taxes payable (3) 4 0 (1) On January 1, 2023, TEC entered into a loan agreement with PGS for PGS’s allocation of outstanding unsecured notes issued by TEC and outstanding short-term borrowings associated with the separation of PGS from TEC on that date. As of September 30, 2023, the note receivable from PGS was a term loan in the principal amount of $ 670 million and a revolving loan in the principal amount of $ 226 million , offset by discounts and issuance costs of $ 7 million. The maturity date for both loans is December 29, 2023 . The note receivable for the term loan bears interest at primarily the stated rate and the revolving loan rate is consistent with the market rate of TEC's commercial paper. See "Separation of PGS from TEC" in Note 1 for further information. (2) Accounts receivable and accounts payable were incurred in the ordinary course of business and do not bear interest. (3) Taxes receivable were due from EUSHI and taxes payable were due to EUSHI. See Note 4 for additional information. The note payable with TECO Energy bears interest at a rate approximating the market rate of TEC's commercial paper.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2023
Accounting Policies [Abstract]
Principles of Consolidation and Basis of Presentation	Principles of Consolidation and Basis of Presentation TEC is a wholly owned subsidiary of TECO Energy, which is an indirect, wholly owned subsidiary of Emera. TEC is comprised of the electric division, referred to as Tampa Electric, and prior to January 1, 2023, the natural gas division, referred to as PGS. See "Separation of PGS from TEC" below for further information. In the opinion of management, the unaudited consolidated condensed financial statements include all adjustments that are of a recurring nature and necessary to state fairly the financial position of TEC as of September 30, 2023 and December 31, 2022, and the results of operations and cash flows for the periods ended September 30, 2023 and 2022. The results of operations for the three and nine months ended September 30, 2023 are not necessarily indicative of the results that can be expected for the entire fiscal year ending December 31, 2023. The use of estimates is inherent in the preparation of financial statements in accordance with U.S. GAAP. Actual results could differ from these estimates. The year-end Consolidated Condensed Balance Sheet was derived from audited financial statements; however, this quarterly report on Form 10-Q does not include all year-end disclosures required for an annual report on Form 10-K by U.S. GAAP.
Separation of PGS from TEC	Separation of PGS from TEC PGS became an operating division of TEC in 1997 when TECO Energy purchased PGS and merged that corporation into TEC. Since then, PGS has operated as a stand-alone regulated utility, including having its own tariffs and its own books and records. On January 1, 2023, TEC transferred the assets and liabilities of its PGS division into a separate corporation called Peoples Gas System, Inc. pursuant to a Contribution Agreement. This new corporation is a wholly owned subsidiary of a newly formed gas operations holding company, TECO Gas Operations, Inc., a wholly owned subsidiary of TECO Energy. On January 1, 2023, the assets, liabilities, and equity that had been recorded in the books of PGS were transferred from TEC to the newly formed company at book value in a tax-free transaction. PGS issued 100 shares of common stock to TEC related to the transfer, which were subsequently distributed to TECO Energy, Inc. and then contributed to TECO Gas Operations, Inc. As a result, from and after January 1, 2023, the PGS division is no longer operated by TEC. This is a transaction between entities under common control; therefore, TEC did no t recognize a gain or loss on the transaction. TEC is not required to recast its prior period financial statements and disclosures to exclude PGS prior to January 1, 2023. The TEC consolidated condensed statement of cash flows for the nine months ended September 30, 2023 does not include the non-cash impact of separating the PGS assets, liabilities and equity from TEC on January 1, 2023 and excludes PGS’s opening cash balance. The impact of the separation of PGS from TEC on the consolidated condensed statements of capital for the nine months ended September 30, 2023 was $ 992 million, which represents the net assets of PGS transferred as of January 1, 2023. TEC recorded $ 121 million to retained earnings, which was the retained earnings of PGS as of January 1, 2023, and the remainder of $ 871 million was recorded to additional paid in capital, which is presented with common stock. Included in the liabilities transferred was PGS’s allocation of outstanding unsecured notes and outstanding short-term borrowings issued by TEC. The obligations related to these combined borrowings are reflected in a loan agreement between TEC and PGS. The initial obligation of PGS under the loan agreement at January 1, 2023 was a term loan in the principal amount of $ 670 million and a revolving loan in the principal amount of $ 66 million. The maturity date for both is December 29, 2023. PGS intends to access the third-party lending market during 2023 but cannot predict when during the year that it will do so. To assist its affiliate and to facilitate an orderly transfer of its gas assets, Tampa Electric will continue to be responsible for providing capital as needed to PGS under a loan agreement. See Note 12 for further information regarding TEC's related party transactions with PGS. For the stand alone PGS balance sheet as of December 31, 2022, see Note 1 of TEC’s Annual Report on Form 10-K for the year ended December 31, 2022.
Receivables and Allowance for Credit Losses	Receivables and Allowance for Credit Losses Receivables on the Consolidated Condensed Balance Sheets include receivables from contracts with customers, which consist of services to residential, commercial, industrial and other customers, totaling $ 362 million and $ 295 million as of September 30, 2023 and December 31, 2022, respectively. An allowance for credit losses is established based on TEC’s collection experience and reasonable and supportable forecasts that affect the collectibility of the reported amount. Circumstances that could affect TEC’s estimates of credit losses include, but are not limited to, customer credit issues, generating fuel prices, customer deposits and general economic conditions. Accounts are reserved in the allowance or written off once they are deemed to be uncollectible. As of September 30, 2023 and December 31, 2022, unbilled revenues of $ 81 million and $ 82 million, respectively, are included in the “Receivables” line item on the Consolidated Condensed Balance Sheets.
Accounting for Franchise Fees and Gross Receipts	Accounting for Franchise Fees and Gross Receipts TEC is allowed to recover certain costs from customers on a dollar-for-dollar basis through rates approved by the FPSC. The amounts included in customers’ bills for franchise fees and gross receipt taxes are included as revenues on the Consolidated Condensed Statements of Income. Franchise fees and gross receipt taxes payable by TEC are included as an expense on the Consolidated Condensed Statements of Income in “Taxes, other than income”. These amounts totaled $ 43 million and $ 41 million for the three months ended September 30, 2023 and 2022, respectively, and totaled $ 106 million and $ 110 million for the nine months ended September 30, 2023 and 2022, respectively.

Regulatory (Tables)

Regulatory (Tables)	9 Months Ended
	Sep. 30, 2023
Regulated Operations [Abstract]
Schedule of Regulatory Assets and Regulatory Liabilities	Details of the regulatory assets and liabilities are presented in the following table: Regulatory Assets and Liabilities (millions) September 30, 2023 December 31, 2022 Regulatory assets: Regulatory tax asset (1) $ 111 $ 124 Cost-recovery clauses (2) 199 525 Capital cost recovery for early retired assets (3) 499 497 Environmental remediation (4) 0 20 Postretirement benefits (5) 238 272 Asset retirement obligation (6) 11 13 Storm reserve (7) 39 76 Other 19 25 Total regulatory assets 1,116 1,552 Less: Current portion 227 361 Long-term regulatory assets $ 889 $ 1,191 Regulatory liabilities: Regulatory tax liability (8) $ 478 $ 601 Cost-recovery clauses - deferred balances (2) 23 30 Accumulated reserve - cost of removal (9) 288 498 Other 24 11 Total regulatory liabilities 813 1,140 Less: Current portion 86 85 Long-term regulatory liabilities $ 727 $ 1,055 (1) The regulatory tax asset is primarily associated with the depreciation and recovery of AFUDC-equity. This asset does not earn a return but rather is included in the capital structure, which is used in the calculation of the weighted cost of capital used to determine revenue requirements. It will be recovered over the expected life of the related assets. (2) These assets and liabilities are related to FPSC clauses and riders, primarily related to the fuel clause and the increase in natural gas prices experienced in 2022. They are recovered or refunded through cost-recovery mechanisms approved by the FPSC on a dollar-for-dollar basis in a subsequent period. (3) This asset is related to the remaining net book value of Big Bend Units 1 through 3 and meter assets that were retired. The balance earns a rate of return as permitted by the FPSC and will be recovered as a separate line item on customer bills for a period of 15 years . See “Tampa Electric Base Rates” above for further information. (4) This asset was related to PGS costs associated with environmental remediation primarily at MGP sites. (5) This asset is related to the deferred costs of postretirement benefits and it is amortized over the remaining service life of plan participants. Deferred costs of postretirement benefits that are included in expense are recognized as cost of service for rate-making purposes as permitted by the FPSC. (6) This asset is related to costs associated with an asset retirement obligation, which is a legal obligation for the future retirement of certain tangible, long-lived assets. This regulatory asset does not earn a return because it is offset with related assets and liabilities within rate base. It is recovered and removed as the obligation is settled and removed as the activities for the retirement of the related assets have been completed. (7) See "Tampa Electric Storm Restoration Cost Recovery" above for information regarding this reserve. The regulatory asset is included in rate base and earns interest as permitted by the FPSC. (8) The regulatory tax liability is primarily related to the revaluation of TEC’s deferred income tax balances recorded on December 31, 2017 at the lower corporate income tax rate due to U.S. tax reform. The liability related to the revaluation of the deferred income tax balances is amortized and returned to customers through rate reductions or other revenue offsets based on IRS regulations and the settlement agreement for tax reform benefits approved by the FPSC. (9) This item represents the non-ARO cost of removal in the accumulated reserve for depreciation. AROs are costs for legally required removal of property, plant and equipment. Non-ARO cost of removal represents estimated funds received from customers through depreciation rates to cover future non-legally required cost of removal of property, plant and equipment, net of salvage value upon retirement, which reduces rate base for ratemaking purposes. This liability is reduced as costs of removal are incurred.

Employee Postretirement Benef_2

Employee Postretirement Benefits (Tables)	9 Months Ended
	Sep. 30, 2023
TECO Energy [Member]
Schedule of Net Periodic Benefit Cost	The following table presents detail related to TECO Energy’s periodic benefit cost for pension and other postretirement benefits. Amounts disclosed for TECO Energy’s pension benefits include the amounts related to its qualified pension plan and non-qualified, non-contributory SERP and Restoration Plan. TECO Energy Benefit Cost (millions) Pension Benefits Other Postretirement Benefits Three months ended September 30, 2023 2022 2023 2022 Components of net periodic benefit cost Service cost $ 3 $ 5 $ 0 $ 0 Interest cost 8 6 2 1 Expected return on assets ( 13 ) ( 13 ) 0 0 Amortization of: Actuarial loss (gain) 2 4 0 1 Net periodic benefit cost $ 0 $ 2 $ 2 $ 2 Nine months ended September 30, Components of net periodic benefit cost Service cost $ 11 $ 14 $ 0 $ 1 Interest cost 26 18 6 4 Expected return on assets ( 40 ) ( 39 ) 0 0 Amortization of: Actuarial loss (gain) 4 13 ( 1 ) 1 Settlement cost (1) 2 1 0 0 Net periodic benefit cost $ 3 $ 7 $ 5 $ 6 (1) Represents TEC's SERP and Restoration Plan settlement charges as a result of the prior retirements of certain executives.

Short-Term Debt (Tables)

Short-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2023
Debt Disclosure [Abstract]
Short-Term Debt Credit Facilities	Details of TEC’s short-term borrowings are presented in the following table: September 30, 2023 December 31, 2022 Borrowings Borrowings Letters Borrowings Borrowings Letters Credit Outstanding - Outstanding - of Credit Credit Outstanding - Outstanding - of Credit (millions) Facilities Credit Facilities (1) Commercial Paper (1) Outstanding Facilities Credit Facilities (1) Commercial Paper (1) Outstanding 5-year facility (2) $ 800 $ 0 $ 758 $ 1 $ 800 $ 0 $ 619 $ 1 1-year term facility (3) 400 400 0 0 400 400 0 0 1-year term facility (4) 200 0 0 0 0 0 0 0 1-year term facility (5) 200 0 0 0 0 0 0 0 Total $ 1,600 $ 400 $ 758 $ 1 $ 1,200 $ 400 $ 619 $ 1 (1) Borrowings outstanding are reported as notes payable. (2) This 5-year facility matures on December 17, 2026 . TEC also has an active commercial paper program for up to $ 800 million, of which the full amount outstanding is backed by TEC’s credit facility. The amount of commercial paper issued results in an equal amount of its credit facility being considered drawn and unavailable. (3) This 1-year term facility was set to mature on December 16, 2022 . On December 13, 2022, TEC extended the maturity date to December 13, 2023. (4) On March 1, 2023, TEC entered into a 1-year term facility that matures on February 28, 2024 . (5) On April 3, 2023, TEC entered into a 1-year term facility that matures on April 1, 2024 .

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2023
Commitments and Contingencies Disclosure [Abstract]
Schedule of Long-term Commitments	The following is a schedule of future payments under PPAs, minimum lease payments with non-cancelable lease terms in excess of one year, and other net purchase obligations/commitments at September 30, 2023: Fuel Long-term Demand Purchased Capital and Service Operating Side (millions) Power Transportation Projects Gas Supply (1) Agreements Leases Management Total 2023 $ 4 $ 31 $ 460 $ 94 $ 8 $ 1 $ 1 $ 599 2024 0 132 163 201 34 3 5 538 2025 0 128 18 69 22 2 4 243 2026 0 125 4 18 23 1 1 172 2027 0 125 1 4 22 1 1 154 Thereafter 0 930 0 1 50 46 0 1,027 Total future minimum payments $ 4 $ 1,471 $ 646 $ 387 $ 159 $ 54 $ 12 $ 2,733 (1) As of September 30, 2023, $ 3 million of fuel and gas supply contractual obligations were held between Tampa Electric and Emera Energy Services, a related party.

Segment Information (Tables)

Segment Information (Tables)	9 Months Ended
	Sep. 30, 2023
Segment Reporting [Abstract]
Schedule of Segment Information	(millions) Tampa Eliminations/ Tampa Electric Three months ended September 30, Electric PGS Reclassifications Company 2023 Revenues - external $ 795 $ 795 Intracompany sales 0 0 Total revenues 795 795 Total interest charges 61 61 Net income $ 170 $ 170 2022 Revenues - external $ 752 $ 160 $ 0 $ 912 Intracompany sales 1 1 ( 2 ) 0 Total revenues 753 161 ( 2 ) 912 Total interest charges 37 7 0 44 Net income $ 153 $ 16 $ 0 $ 169 Nine months ended September 30, 2023 Revenues - external $ 2,024 $ 2,024 Intracompany sales 0 0 Total revenues 2,024 2,024 Total interest charges 180 180 Net income $ 381 $ 381 2022 Revenues - external $ 1,923 $ 501 $ 0 $ 2,424 Intracompany sales 3 3 ( 6 ) 0 Total revenues 1,926 504 ( 6 ) 2,424 Total interest charges 99 18 0 117 Net income $ 367 $ 65 $ 0 $ 432 Total assets at September 30, 2023 $ 13,286 $ ( 648 ) (1) $ 12,638 Total assets at December 31, 2022 $ 12,064 $ 2,471 (2) $ ( 732 ) (1) $ 13,803 (1) Amounts primarily relate to consolidated deferred tax reclassifications. Deferred tax assets are reclassified and netted with deferred tax liabilities upon consolidation. (2) For the summary of the assets and liabilities of PGS as of December 31, 2022, see Note 1 of TEC’s Annual Report on Form 10-K for the year ended December 31, 2022.

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2023
Revenue Recognition [Abstract]
Summary of Disaggregates TEC Revenue by Major Source	The following disaggregates TEC’s revenue by major source: (millions) Tampa Tampa Electric Three months ended September 30, 2023 Electric PGS Eliminations Company Electric revenue Residential $ 567 $ 567 Commercial 234 234 Industrial 56 56 Regulatory deferrals ( 137 ) ( 137 ) Unbilled revenue ( 8 ) ( 8 ) Other (1) 83 83 Total electric revenue 795 795 Total revenue $ 795 $ 795 Three months ended September 30, 2022 Electric revenue Residential $ 445 $ 0 $ 0 $ 445 Commercial 194 0 0 194 Industrial 45 0 0 45 Regulatory deferrals ( 11 ) 0 0 ( 11 ) Unbilled revenue ( 12 ) 0 0 ( 12 ) Other (1) 92 ` 0 ( 1 ) 91 Total electric revenue 753 0 ( 1 ) 752 Gas revenue Residential 0 47 0 47 Commercial 0 46 0 46 Industrial (2) 0 7 0 7 Other (3) 0 61 ( 1 ) 60 Total gas revenue 0 161 ( 1 ) 160 Total revenue $ 753 $ 161 $ ( 2 ) $ 912 (millions) Tampa Tampa Electric Nine months ended September 30, 2023 Electric PGS Eliminations Company Electric revenue Residential $ 1,322 $ 1,322 Commercial 605 605 Industrial 152 152 Regulatory deferrals ( 297 ) ( 297 ) Unbilled revenue 16 16 Other (1) 226 226 Total electric revenue 2,024 2,024 Total revenue $ 2,024 $ 2,024 Nine months ended September 30, 2022 Electric revenue Residential $ 1,063 $ 0 $ 0 $ 1,063 Commercial 501 0 0 501 Industrial 129 0 0 129 Regulatory deferrals ( 17 ) 0 0 ( 17 ) Unbilled revenue 13 0 0 13 Other (1) 237 0 ( 3 ) 234 Total electric revenue 1,926 0 ( 3 ) 1,923 Gas revenue Residential 0 172 0 172 Commercial 0 151 0 151 Industrial (2) 0 22 0 22 Other (3) 0 159 ( 3 ) 156 Total gas revenue 0 504 ( 3 ) 501 Total revenue $ 1,926 $ 504 $ ( 6 ) $ 2,424 (1) Other electric revenue includes sales to public authorities, off-system sales to other utilities and various other items. (2) Industrial gas revenue includes sales to power generation customers. Other gas revenue includes off-system sales to other utilities and various other items.

Related Party Transactions (Tab

Related Party Transactions (Tables)	9 Months Ended
	Sep. 30, 2023
Related Party Transactions [Abstract]
Schedule of Related Party Transactions	A summary of activities between TEC and its affiliates follows: Net transactions with affiliates Three months ended September 30, Nine months ended September 30, (millions) 2023 2022 2023 2022 Natural gas purchases (net of sales) from affiliates $ 21 $ 71 $ 57 $ 185 Services to/(from) affiliates 8 ( 1 ) 23 ( 4 ) Interest income from affiliates 10 0 28 0 Interest expense to affiliates 3 0 8 0 Equity contributions from TECO Energy 100 190 300 470 Dividends to TECO Energy 132 146 302 348 Amounts due from or to affiliates (millions) September 30, 2023 December 31, 2022 Note receivable from PGS (1) $ 889 $ 0 Interest receivable from PGS (1) 4 0 Accounts receivable related to asset management agreements to Emera Energy Services Inc. (2) 4 7 Accounts receivable excluding asset management agreements (2) 11 5 Taxes receivable (3) 0 10 Accounts payable (2) 14 31 Note payable to TECO Energy (4) 195 195 Interest payable to TECO Energy (4) 1 0 Taxes payable (3) 4 0 (1) On January 1, 2023, TEC entered into a loan agreement with PGS for PGS’s allocation of outstanding unsecured notes issued by TEC and outstanding short-term borrowings associated with the separation of PGS from TEC on that date. As of September 30, 2023, the note receivable from PGS was a term loan in the principal amount of $ 670 million and a revolving loan in the principal amount of $ 226 million , offset by discounts and issuance costs of $ 7 million. The maturity date for both loans is December 29, 2023 . The note receivable for the term loan bears interest at primarily the stated rate and the revolving loan rate is consistent with the market rate of TEC's commercial paper. See "Separation of PGS from TEC" in Note 1 for further information. (2) Accounts receivable and accounts payable were incurred in the ordinary course of business and do not bear interest. (3) Taxes receivable were due from EUSHI and taxes payable were due to EUSHI. See Note 4 for additional information. The note payable with TECO Energy bears interest at a rate approximating the market rate of TEC's commercial paper.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)		3 Months Ended		9 Months Ended
	Jan. 01, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Summary Of Significant Accounting Policies [Line Items]
Issuance of common stock on transfer of assets	100
Gain (loss) from transaction	$ 0
Receivables from contracts with customers		$ 362,000,000		$ 362,000,000		$ 295,000,000
Unbilled revenues		81,000,000		81,000,000		82,000,000
Franchise fees and gross receipts taxes		43,000,000	$ 41,000,000	106,000,000	$ 110,000,000
Separation of PGS equity from TEC				992,000,000
Retained earnings	121,000,000	$ 304,000,000		304,000,000		$ 346,000,000
Additional Paid in capital	871,000,000
TECO Energy [Member]
Summary Of Significant Accounting Policies [Line Items]
Separation of PGS equity from TEC				$ 992,000,000
Term Loan [Member]
Summary Of Significant Accounting Policies [Line Items]
Principal amount	670,000,000
Revolving Loan [Member]
Summary Of Significant Accounting Policies [Line Items]
Principal amount	$ 66,000,000

Regulatory - Additional Informa

Regulatory - Additional Information (Detail) - USD ($)

1 Months Ended

9 Months Ended

12 Months Ended

Nov. 09, 2023

Jan. 23, 2023

Jul. 01, 2022

Aug. 06, 2021

Oct. 31, 2013

Jan. 31, 2024

Sep. 30, 2023

Jan. 31, 2023

Nov. 30, 2022

Sep. 30, 2022

Jan. 31, 2022

Sep. 30, 2023

Dec. 31, 2021

Dec. 31, 2020

Dec. 31, 2019

Dec. 31, 2022

Public Utilities General Disclosures [Line Items]

Base rate adjustment amount

$ 10,000,000

Adjustments to fuel charges recovery

$ 518,000,000

Adjustments to fuel charges recovery projected reduction

$ 170,000,000

Accumulated depreciation

$ 3,367,000,000

$ 3,367,000,000

$ 3,845,000,000

Additional cost recovery from settlement agreement

$ 169,000,000

Settlement Agreement [Member]

Public Utilities General Disclosures [Line Items]

Base rate adjustment amount

$ 123,000,000

Increase in revenue

$ 191,000,000

Settlement agreement number of subsequent years adjustments

2 years

Settlement agreement adjustment amount

$ 90,000,000

Allowed equity in the capital structure

54%

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] | 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] | Settlement Agreement [Member]

Public Utilities General Disclosures [Line Items]

Percentage of ROE

9%

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] | Settlement Agreement [Member]

Public Utilities General Disclosures [Line Items]

Percentage of ROE

11%

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] | 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

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

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

$ 129,000,000

Storm reserve expected to charge

$ 121,000,000

Storm restoration costs charged to reserve

10,000,000

Replenishment of balance in reserve

$ 131,000,000

$ 56,000,000

Hurricane Ian [Member] | Subsequent Event [Member]

Public Utilities General Disclosures [Line Items]

Storm restoration costs

$ 134,000,000

Storm restoration costs balance

$ 29,000,000

Hurricane Nicole [Member]

Public Utilities General Disclosures [Line Items]

Restoration costs

$ 2,000,000

Hurricane Idalia [Member]

Public Utilities General Disclosures [Line Items]

Storm restoration costs

$ 36,000,000

Regulatory - Schedule of Regula

Regulatory - Schedule of Regulatory Assets and Regulatory Liabilities (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Regulatory assets:
Regulatory assets	$ 1,116	$ 1,552
Less: Current portion	227	361
Long-term regulatory assets	889	1,191
Regulatory liabilities:
Regulatory liabilities	813	1,140
Less: Current portion	86	85
Long-term regulatory liabilities	727	1,055
Regulatory Tax Asset [Member]
Regulatory assets:
Regulatory assets	111	124
Cost-Recovery Clauses [Member]
Regulatory assets:
Regulatory assets	199	525
Capital Cost Recovery for Early Retired Assets [Member]
Regulatory assets:
Regulatory assets	499	497
Environmental Remediation [Member]
Regulatory assets:
Regulatory assets	0	20
Postretirement Benefits [Member]
Regulatory assets:
Regulatory assets	238	272
Asset Retirement Obligation [Member]
Regulatory assets:
Regulatory assets	11	13
Storm Reserve [Member]
Regulatory assets:
Regulatory assets	39	76
Other [Member]
Regulatory assets:
Regulatory assets	19	25
Regulatory Tax Liability [Member] | Non-Current Liabilities [Member]
Regulatory liabilities:
Regulatory liabilities	478	601
Cost-recovery Clauses - Deferred Balances [Member]
Regulatory liabilities:
Regulatory liabilities	23	30
Accumulated Reserve - Cost of Removal [Member]
Regulatory liabilities:
Regulatory liabilities	288	498
Other [Member]
Regulatory liabilities:
Regulatory liabilities	$ 24	$ 11

Regulatory - Schedule of Regu_2

Regulatory - Schedule of Regulatory Assets and Regulatory Liabilities (Parenthetical) (Detail)	9 Months Ended
	Sep. 30, 2023
Capital Cost Recovery for Early Retired Assets [Member]
Schedule Of Regulatory Assets And Liabilities [Line Items]
Settlement agreement cost recovery period	15 years

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Income Taxes [Line Items]
Regulatory liability due to obligation to transfer tax rate reduction expense benefit	$ 20
Effective tax rate	15.70%	19.70%
Unrecognized tax benefit that would reduce effective tax rate	$ 9		$ 9

Employee Postretirement Benef_3

Employee Postretirement Benefits - Schedule of Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Pension Benefits [Member]
Amortization of:
Net periodic benefit cost		$ 0	$ 1	$ 1	$ 5
Other Postretirement Benefits [Member]
Amortization of:
Net periodic benefit cost		1	2	4	7
TECO Energy [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		3	5	11	14
Interest cost		8	6	26	18
Expected return on assets		(13)	(13)	(40)	(39)
Amortization of:
Actuarial loss (gain)		2	4	4	13
Settlement cost	[1]			2	1
Net periodic benefit cost		0	2	3	7
TECO Energy [Member] | Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		0	0	0	1
Interest cost		2	1	6	4
Expected return on assets		0	0	0	0
Amortization of:
Actuarial loss (gain)		0	1	(1)	1
Settlement cost	[1]			0	0
Net periodic benefit cost		$ 2	$ 2	$ 5	$ 6
[1] Represents TEC's SERP and Restoration Plan settlement charges as a result of the prior retirements of certain executives.

Employee Postretirement Benef_4

Employee Postretirement Benefits - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Defined Benefit Plan Disclosure [Line Items]
Reclassification of regulatory assets to net income as part of periodic benefit cost	$ 0	$ 5	$ 1	$ 14
TECO Energy [Member]
Defined Benefit Plan Disclosure [Line Items]
Long-term EROA			7.05%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	0	1	$ 1	5
Employer contributions			10	15
Pension Benefits [Member] | TECO Energy [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	0	2	$ 3	7
Discount rate			5.55%
Employer contributions			$ 16	19
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	1	2	4	7
Other Postretirement Benefits [Member] | TECO Energy [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	$ 2	$ 2	$ 5	$ 6
Discount rate			5.53%

Short-Term Debt - Credit Facili

Short-Term Debt - Credit Facilities (Detail) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Line Of Credit Facility [Line Items]
Credit Facilities	$ 1,600,000,000	$ 1,200,000,000
Borrowings Outstanding	1,158,000,000	1,019,000,000
Letters of Credit Outstanding	1,000,000	1,000,000
Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Letters of Credit Outstanding	400,000,000	400,000,000
Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	758,000,000	619,000,000
December 13, 2023 [Member] | Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Letters of Credit Outstanding		400,000,000
5-year Facility [Member] | December 17, 2026 [Member]
Line Of Credit Facility [Line Items]
Credit Facilities	800,000,000	800,000,000
Letters of Credit Outstanding	1,000,000	1,000,000
5-year Facility [Member] | December 17, 2026 [Member] | Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Letters of Credit Outstanding	0	0
5-year Facility [Member] | December 17, 2026 [Member] | Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	758,000,000	619,000,000
1-year Term Facility [Member] | December 13, 2023 [Member]
Line Of Credit Facility [Line Items]
Credit Facilities	400,000,000	400,000,000
Letters of Credit Outstanding	0	0
1-year Term Facility [Member] | December 13, 2023 [Member] | Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Letters of Credit Outstanding	400,000,000
1-year Term Facility [Member] | December 13, 2023 [Member] | Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	0	0
1-year Term Facility [Member] | February 28, 2024 [Member]
Line Of Credit Facility [Line Items]
Credit Facilities	200,000,000	0
Letters of Credit Outstanding	0	0
1-year Term Facility [Member] | February 28, 2024 [Member] | Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Letters of Credit Outstanding	0	0
1-year Term Facility [Member] | February 28, 2024 [Member] | Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	0	0
1-year Term Facility [Member] | April 1, 2024 [Member]
Line Of Credit Facility [Line Items]
Credit Facilities	200,000,000	0
Letters of Credit Outstanding	0	0
1-year Term Facility [Member] | April 1, 2024 [Member] | Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Letters of Credit Outstanding	0	0
1-year Term Facility [Member] | April 1, 2024 [Member] | Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	$ 0	$ 0

Short-Term Debt - Credit Faci_2

Short-Term Debt - Credit Facilities (Parenthetical) (Detail) - USD ($)			9 Months Ended	12 Months Ended
	Apr. 03, 2023	Mar. 01, 2023	Sep. 30, 2023	Dec. 31, 2022
5-year Facility [Member]
Line Of Credit Facility [Line Items]
Credit facility maturity date			Dec. 17, 2026	Dec. 17, 2026
1-year Term Facility [Member]
Line Of Credit Facility [Line Items]
Credit facility maturity date	Apr. 01, 2024	Feb. 28, 2024	Dec. 16, 2022	Dec. 16, 2022
Maximum [Member] | Commercial Paper Program [Member]
Line Of Credit Facility [Line Items]
Commercial paper issued			$ 800,000,000

Short-Term Debt - Additional In

Short-Term Debt - Additional Information (Detail) - USD ($)			9 Months Ended
	Apr. 03, 2023	Mar. 01, 2023	Sep. 30, 2023	Dec. 31, 2022
Line Of Credit Facility [Line Items]
Commitment fees, percentage			0.125%
Weighted-average interest rate			5.85%	5%
Line of credit facility maximum borrowing capacity			$ 1,600,000,000	$ 1,200,000,000
364-day Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity	$ 200,000,000	$ 200,000,000
Credit facility maturity date	Apr. 01, 2024	Feb. 28, 2024

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Long-term debt	$ 3,735	$ 3,734
Estimated fair value	$ 3,046	$ 3,234

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Long-term Commitments (Detail) $ in Millions	Sep. 30, 2023 USD ($)
Other Commitments [Line Items]
2023	$ 599
2024	538
2025	243
2026	172
2027	154
Thereafter	1,027
Total future minimum payments	2,733
Purchased Power [Member]
Other Commitments [Line Items]
2023	4
2024	0
2025	0
2026	0
2027	0
Thereafter	0
Total future minimum payments	4
Transportation [Member]
Other Commitments [Line Items]
2023	31
2024	132
2025	128
2026	125
2027	125
Thereafter	930
Total future minimum payments	1,471
Capital Projects [Member]
Other Commitments [Line Items]
2023	460
2024	163
2025	18
2026	4
2027	1
Thereafter	0
Total future minimum payments	646
Fuel and Gas Supply [Member]
Other Commitments [Line Items]
2023	94
2024	201
2025	69
2026	18
2027	4
Thereafter	1
Total future minimum payments	387
Long-term Service Agreements [Member]
Other Commitments [Line Items]
2023	8
2024	34
2025	22
2026	23
2027	22
Thereafter	50
Total future minimum payments	159
Operating Leases [Member]
Other Commitments [Line Items]
2023	1
2024	3
2025	2
2026	1
2027	1
Thereafter	46
Total future minimum payments	54
Demand Side Management [Member]
Other Commitments [Line Items]
2023	1
2024	5
2025	4
2026	1
2027	1
Thereafter	0
Total future minimum payments	$ 12

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Long-term Commitments (Parenthetical) (Detail) $ in Millions	Sep. 30, 2023 USD ($)
Other Commitments [Line Items]
Contractual obligations	$ 2,733
Fuel And Gas Supply [Member]
Other Commitments [Line Items]
Contractual obligations	387
Fuel And Gas Supply [Member] | Tampa Electric [Member]
Other Commitments [Line Items]
Contractual obligations	$ 3

Segment Information - Additiona

Segment Information - Additional Infomation (Detail)	9 Months Ended
	Sep. 30, 2023 Segment
Segment Reporting [Abstract]
Number of operating segments	1
Number of reportable segments	1

Segment Information - Schedule

Segment Information - Schedule of Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Segment Reporting Information [Line Items]
Total revenues	$ 795	$ 912	$ 2,024	$ 2,424
Total interest charges	61	44	180	117
Net income	170	169	381	432
Total assets	12,638		12,638		$ 13,803
Revenues - External [Member]
Segment Reporting Information [Line Items]
Total revenues	795	912	2,024	2,424
Related Party [Member]
Segment Reporting Information [Line Items]
Total interest charges	3	0	8	0
Intracompany Sales [Member]
Segment Reporting Information [Line Items]
Total revenues	0
Intracompany Sales [Member] | Related Party [Member]
Segment Reporting Information [Line Items]
Total revenues		0	0	0
Eliminations/Reclassifications [Member]
Segment Reporting Information [Line Items]
Total revenues		(2)		(6)
Total interest charges		0		0
Net income		0		0
Total assets	(648)		(648)		(732)
Eliminations/Reclassifications [Member] | Revenues - External [Member]
Segment Reporting Information [Line Items]
Total revenues		0		0
Eliminations/Reclassifications [Member] | Intracompany Sales [Member] | Related Party [Member]
Segment Reporting Information [Line Items]
Total revenues		(2)		(6)
Tampa Electric [Member]
Segment Reporting Information [Line Items]
Total revenues	795	753	2,024	1,926
Tampa Electric [Member] | Intracompany Sales [Member] | Related Party [Member]
Segment Reporting Information [Line Items]
Total revenues	0
Tampa Electric [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	795	753	2,024	1,926
Total interest charges	61	37	180	99
Net income	170	153	381	367
Total assets	13,286		13,286		12,064
Tampa Electric [Member] | Operating Segments [Member] | Revenues - External [Member]
Segment Reporting Information [Line Items]
Total revenues	$ 795	752	2,024	1,923
Tampa Electric [Member] | Operating Segments [Member] | Intracompany Sales [Member] | Related Party [Member]
Segment Reporting Information [Line Items]
Total revenues		1	$ 0	3
PGS [Member]
Segment Reporting Information [Line Items]
Total revenues		161		504
PGS [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues		161		504
Total interest charges		7		18
Net income		16		65
Total assets					$ 2,471
PGS [Member] | Operating Segments [Member] | Revenues - External [Member]
Segment Reporting Information [Line Items]
Total revenues		160		501
PGS [Member] | Operating Segments [Member] | Intracompany Sales [Member] | Related Party [Member]
Segment Reporting Information [Line Items]
Total revenues		$ 1		$ 3

Revenue - Summary of Disaggrega

Revenue - Summary of Disaggregates TEC Revenue by Major Source (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Disaggregation Of Revenue [Line Items]
Total electric revenue	$ 795	$ 752	$ 2,024	$ 1,923
Total gas revenue	0	160	0	501
Total revenue	795	912	2,024	2,424
Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	567	445	1,322	1,063
Total gas revenue		47		172
Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	234	194	605	501
Total gas revenue		46		151
Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	56	45	152	129
Total gas revenue		7		22
Regulatory Deferrals [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(137)	(11)	(297)	(17)
Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(8)	(12)	16	13
Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	83	91	226	234
Total gas revenue		60		156
Eliminations [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		(1)		(3)
Total gas revenue		(1)		(3)
Total revenue		(2)		(6)
Eliminations [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Total gas revenue		0		0
Eliminations [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Total gas revenue		0		0
Eliminations [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Total gas revenue		0		0
Eliminations [Member] | Regulatory Deferrals [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Eliminations [Member] | Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Eliminations [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		(1)		(3)
Total gas revenue		(1)		(3)
Tampa Electric [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	795	753	2,024	1,926
Total gas revenue		0		0
Total revenue	795	753	2,024	1,926
Tampa Electric [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	567	445	1,322	1,063
Total gas revenue		0		0
Tampa Electric [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		194	605	501
Total gas revenue	234	0		0
Tampa Electric [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	56	45	152	129
Total gas revenue		0		0
Tampa Electric [Member] | Regulatory Deferrals [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(137)	(11)	(297)	(17)
Tampa Electric [Member] | Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(8)	(12)	16	13
Tampa Electric [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	$ 83	92	$ 226	237
Total gas revenue		0		0
PGS [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Total gas revenue		161		504
Total revenue		161		504
PGS [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Total gas revenue		47		172
PGS [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Total gas revenue		46		151
PGS [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Total gas revenue		7		22
PGS [Member] | Regulatory Deferrals [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
PGS [Member] | Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
PGS [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0		0
Total gas revenue		$ 61		$ 159

Revenue - Additional Informatio

Revenue - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2023	Dec. 31, 2022
Regulated Operating Revenue [Abstract]
Remaining performance obligations, transaction price	$ 62	$ 140
Remaining performance obligations, expected year of revenue recognition	2043

Related Party Transactions - Sc

Related Party Transactions - Schedule of Related Parties (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Related Party Transaction [Line Items]
Natural gas purchases (net of sales) from affiliates	$ 21	$ 71	$ 57	$ 185
Services to/(from) affiliates	8	(1)	23	(4)
Interest expense to affiliates	61	44	180	117
Dividends to TECO Energy			302	348
Equity contributions from TECO Energy			300	470
Related Party [Member]
Related Party Transaction [Line Items]
Interest income from affiliates	10	0	28	0
Interest expense to affiliates	3	0	8	0
PGS [Member]
Related Party Transaction [Line Items]
Interest receivable from PGS	4		4		$ 0
PGS [Member] | Related Party [Member]
Related Party Transaction [Line Items]
Note receivable from PGS	889		889		0
Affiliate [Member]
Related Party Transaction [Line Items]
Accounts receivable excluding asset management agreements	11		11		5
Taxes receivable	0		0		10
Accounts payable	14		14		31
Note payable to TECO Energy	195		195		195
Interest payable to TECO Energy	1		1		0
Taxes payable	4		4		0
Emera Energy Services Inc [Member]
Related Party Transaction [Line Items]
Accounts receivable related to asset management agreements to Emera Energy Services Inc.	4		4		$ 7
TECO Energy [Member]
Related Party Transaction [Line Items]
Dividends to TECO Energy	132	146	302	348
Equity contributions from TECO Energy	$ 100	$ 190	$ 300	$ 470

Related Party Transactions - _2

Related Party Transactions - Schedule of Related Parties (Parenthetical) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2023	Jan. 01, 2023
PGSI [Member]
Related Party Transaction [Line Items]
Debt discounts and issuance costs, net	$ 7
Term Loan [Member]
Related Party Transaction [Line Items]
Principal amount		$ 670
Term Loan [Member] | PGSI [Member]
Related Party Transaction [Line Items]
Principal amount	670
Revolving Loan [Member]
Related Party Transaction [Line Items]
Principal amount		$ 66
Revolving Loan [Member] | PGSI [Member]
Related Party Transaction [Line Items]
Principal amount	$ 226
Term Loan and Revolving Loan [Member] | PGSI [Member]
Related Party Transaction [Line Items]
Debt instrument maturity date	Dec. 29, 2023