Tampa Electric 10-Q 11 Aug 21 2021 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2021	Aug. 10, 2021
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
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	Jun. 30, 2021	Dec. 31, 2020
Property, plant and equipment
Utility plant, at original costs	$ 14,346	$ 13,818
Accumulated depreciation	(3,897)	(3,712)
Utility plant, net	10,449	10,106
Other property	14	14
Total property, plant and equipment, net	10,463	10,120
Current assets
Cash and cash equivalents	24	10
Receivables, less allowance for credit losses of $8 and $7 at June 30, 2021 and December 31, 2020, respectively	265	219
Due from affiliates	10	11
Inventories, at average cost
Regulatory assets	68	79
Prepayments and other current assets	22	10
Total current assets	524	462
Deferred debits
Regulatory assets	413	406
Other	59	60
Total deferred debits	472	466
Total assets	11,459	11,048
Capitalization
Common stock	4,180	3,890
Accumulated other comprehensive loss	(1)	(1)
Retained earnings	359	327
Total capital	4,538	4,216
Long-term debt	3,385	2,594
Total capitalization	7,923	6,810
Current liabilities
Long-term debt due within one year	0	278
Notes payable	410	775
Accounts payable	264	321
Due to affiliates	22	46
Customer deposits	130	130
Regulatory liabilities	57	67
Accrued interest	20	13
Accrued taxes	63	22
Other	43	57
Total current liabilities	1,009	1,709
Long-term liabilities
Deferred income taxes	815	783
Regulatory liabilities	1,156	1,194
Investment tax credits	233	216
Deferred credits and other liabilities	323	336
Total long-term liabilities	2,527	2,529
Commitments and Contingencies (see Note 8)
Total liabilities and capitalization	11,459	11,048
Fuel [Member]
Inventories, at average cost
Utility inventories	21	26
Materials and Supplies [Member]
Inventories, at average cost
Utility inventories	114	107
Electric [Member]
Property, plant and equipment
Utility plant, at original costs	11,876	11,486
Gas [Member]
Property, plant and equipment
Utility plant, at original costs	$ 2,470	$ 2,332

Consolidated Condensed Balanc_2

Consolidated Condensed Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Allowance for credit losses	$ 8	$ 7

Consolidated Condensed Statemen

Consolidated Condensed Statements of Income and Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues
Electric	$ 531	$ 453	$ 977	$ 873
Gas	123	96	276	223
Total revenues	654	549	1,253	1,096
Expenses
Fuel	129	67	238	168
Purchased power	26	25	44	27
Cost of natural gas sold	33	25	83	67
Operations and maintenance	139	126	267	260
Depreciation and amortization	107	92	213	189
Taxes, other than income	56	50	110	101
Total expenses	490	385	955	812
Income from operations	164	164	298	284
Other income
Allowance for equity funds used during construction	10	7	20	13
Other income, net	2	2	3	3
Total other income	12	9	23	16
Interest charges
Interest expense	39	35	77	72
Allowance for borrowed funds used during construction	(5)	(3)	(10)	(6)
Total interest charges	34	32	67	66
Income before provision for income taxes	142	141	254	234
Provision for income taxes	21	24	41	40
Net income	121	117	213	194
Comprehensive income	$ 121	$ 117	$ 213	$ 194

Consolidated Condensed Statem_2

Consolidated Condensed Statements of Cash Flows (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities
Net income	$ 213	$ 194
Adjustments to reconcile net income to cash from operating activities:
Depreciation and amortization	213	189
Deferred income taxes and investment tax credits	27	43
Allowance for equity funds used during construction	(20)	(13)
Deferred recovery clauses	(10)	37
Receivables, less allowance for credit losses	(43)	(22)
Prepayments and other deposits	(11)	(9)
Taxes accrued	20	20
Accounts payable	(45)	(41)
Regulatory assets and liabilities	(2)	(12)
Other	4	(4)
Cash flows from operating activities	346	382
Cash flows used in investing activities
Capital expenditures	(588)	(653)
Net proceeds from sale of assets	0	6
Cash flows used in investing activities	(588)	(647)
Cash flows from financing activities
Equity contributions from Parent	290	265
Proceeds from long-term debt issuance	790	0
Repayment of long-term debt	(278)	0
Net decrease in short-term debt (maturities of 90 days or less)	(65)	(154)
Proceeds from other short-term debt (maturities over 90 days)	0	300
Repayment of other short-term debt (maturities over 90 days)	(300)	0
Dividends to Parent	(181)	(150)
Cash flows from financing activities	256	261
Net increase (decrease) in cash and cash equivalents	14	(4)
Cash and cash equivalents at beginning of period	10	14
Cash and cash equivalents at end of period	24	10
Supplemental disclosure of non-cash activities
Change in accrued capital expenditures	$ (20)	$ (12)

Consolidated Condensed Statem_3

Consolidated Condensed Statements of Capital (Unaudited) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Beginning balance	$ 4,375	$ 3,845	$ 4,216	$ 3,695
Net income	121	117	213	194
Equity contributions from Parent	135	120	290	265
Dividends to Parent	(93)	(77)	(181)	(150)
Other		(2)		(1)
Ending balance	4,538	4,003	4,538	4,003
Common Stock [Member]
Beginning balance	$ 4,045	$ 3,530	$ 3,890	$ 3,385
Beginning balance	10	10	10	10
Equity contributions from Parent	$ 135	$ 120	$ 290	$ 265
Ending balance	$ 4,180	$ 3,650	$ 4,180	$ 3,650
Ending balance	10	10	10	10
Retained Earnings [Member]
Beginning balance	$ 331	$ 316	$ 327	$ 311
Net income	121	117	213	194
Dividends to Parent	(93)	(77)	(181)	(150)
Other		(2)		(1)
Ending balance	359	354	359	354
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	6 Months Ended
	Jun. 30, 2021
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, 2020 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 the natural gas division, referred to as PGS. Intercompany balances and transactions within the divisions have been eliminated in consolidation. 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 June 30, 2021 and December 31, 2020, and the results of operations and cash flows for the periods ended June 30, 2021 and 2020. The results of operations for the three and six months ended June 30, 2021 are not necessarily indicative of the results that can be expected for the entire fiscal year ending December 31, 2021. 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. Since 2020, the outbreak of COVID-19 has resulted in governments worldwide enacting emergency measures to combat the spread of the virus. While management considered the impact of the COVID-19 pandemic in TEC’s estimates and results, the financial statements as of June 30, 2021 and December 31, 2020 and for the three and six months ended June 30, 2021 and 2020 were not materially impacted by the COVID-19 pandemic. Receivables and Allowance for Credit Losses Receivables from contracts with customers, which consist of services to residential, commercial, industrial and other customers, were $258 million and $214 million as of June 30, 2021 and December 31, 2020, 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 Tampa Electric’s and PGS’s estimates of credit losses include, but are not limited to, customer credit issues, generating fuel prices, customer deposits and general economic conditions, including the impacts of the COVID-19 pandemic. Accounts are reserved in the allowance or written off once they are deemed to be uncollectible. As of June 30, 2021 and December 31, 2020, unbilled revenues of $83 million and $73 million, respectively, are included in the “Receivables” line item on the Consolidated Condensed Balance Sheets. Accounting for Franchise Fees and Gross Receipts Tampa Electric and PGS are 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 Tampa Electric and PGS are included as an expense on the Consolidated Condensed Statements of Income in “Taxes, other than income”. These amounts totaled $31 million and $26 million for the three months ended June 30, 2021 and 2020, respectively, and totaled $60 million and $53 million for the six months ended June 30, 2021 and 2020, respectively.

New Accounting Pronouncements

New Accounting Pronouncements	6 Months Ended
	Jun. 30, 2021
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, are consistent with those disclosed in TEC’s Annual Report on Form 10-K for the year ended December 31, 2020 .

Regulatory

Regulatory	6 Months Ended
	Jun. 30, 2021
Regulated Operations [Abstract]
Regulatory	3. Regulatory Tampa Electric Base Rates On September 27, 2017, Tampa Electric filed with the FPSC an amended and restated settlement agreement that replaced the existing 2013 base rate settlement agreement and extended it another four years through December 31, 2021. The FPSC approved the agreement on November 6, 2017. The amended agreement provides for SoBRAs for TEC’s investments in up to 600 MW of cost-effective solar generation. Tampa Electric has invested approximately $850 million during 2017 through 2021 related to 600 MW of solar projects recoverable under the SoBRAs, and AFUDC was accrued during construction. On December 12, 2017, TEC filed its first petition regarding the SoBRAs along with supporting tariffs demonstrating the cost-effectiveness of the September 1, 2018 tranche representing 145 MW and $24 million annually in estimated revenue requirements. The FPSC approved the tariffs on the first SoBRA filing on May 8, 2018 and TEC began receiving these revenues in September 2018 requirements. The FPSC approved the tariffs on the second SoBRA filing on October 29, 2018 and TEC began receiving these revenues in January 2019. On June 28, 2019, TEC filed its third SoBRA petition along with supporting tariffs demonstrating the cost-effectiveness of the January 1, 2020 tranche representing 149 MW and $26 million annually in estimated revenue requirements. The FPSC approved the tariffs on this SoBRA filing, including an adjustment to reflect the reduction in the state corporate income tax discussed below, on December 10, 2019 and TEC began receiving these revenues in January 2020. On July 31, 2020, TEC filed its fourth and final SoBRA petition along with supporting tariffs demonstrating the cost-effectiveness of the January 1, 2021 tranche representing 46 MW and $8 million annually in estimated revenues. The FPSC approved the tariffs on this SoBRA filing on November 3, 2020 and TEC began receiving these revenues in January 2021. The true-up filing for SoBRA tranche 1 and 2 revenue requirement estimates that were included in base rates as of September 2018 and January 2019, respectively, was submitted on April 30, 2020, and the FPSC approved the amount on August 18, 2020. The $5 million true-up was returned to customers in 2020. The true-up filing for SoBRA tranche 3, included in base rates as of January 2020, was submitted to the FPSC on May 27, 2021. An estimated $4 million true-up is being returned to customers during 2021. The true-up for SoBRA tranche 4 will be filed in 2022. On August 6, 2021, TEC 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 TEC and the intervenors in TEC’s rate case filed with the FPSC in April 2021. The Settlement Agreement agrees 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 includes 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 will continue to be 54% from investor sources of capital. The Settlement Agreement includes 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 not change from January 1, 2022 through December 31, 2024, unless TEC’s earned ROE was to fall below the bottom of the range during that time. The Settlement Agreement contains a provision whereby TEC agrees 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 creates 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 this agreement. The Settlement Agreement would not become effective unless and until approved by the FPSC, which is expected to consider the matter by October 2021. Tampa Electric Big Bend Modernization Project Tampa Electric expects to invest approximately $850 million during 2018 through 2023 to modernize the Big Bend Power Station, of which approximately $611 million has been invested through June 30, 2021. The Big Bend modernization project will repower Big Bend Unit 1 with natural gas combined-cycle technology and eliminate coal as this unit’s fuel. As part of the Big Bend modernization project, on June 1, 2020, Tampa Electric retired the Unit 1 components that will not be used in the modernized plant. At June 30, 2021 and December 31, 2020, Tampa Electric’s balance sheet included $200 million in electric utility plant and $91 million and $88 million, respectively, in accumulated depreciation related to Unit 1 components. In accordance with Tampa Electric’s 2017 settlement agreement approved by the FPSC, Tampa Electric will continue to account for its existing investment in Unit 1 in electric utility plant and depreciate the assets using the current depreciation rates until December 31, 2021. In addition, Tampa Electric plans to retire Big Bend Unit 2 in 2021 as part of the Big Bend modernization project. Tampa Electric plans to retire Big Bend Unit 3 in 2023 as it is in the best interest of customers from economic, environmental risk and operational perspectives. Similar to the retirement plan for Unit 1 and Unit 2, Tampa Electric will continue to account for its existing investment in Unit 3 in electric utility plant and depreciate the assets using the current depreciation rates until December 31, 2021 . On December 30, 2020, Tampa Electric filed a depreciation and dismantlement study and request for capital recovery schedule for all three units with the FPSC. Tampa Electric’s Settlement Agreement provides recovery for the Big Bend Modernization project in two phases. The first phase is a revenue increase to cover the costs of the assets in service during 2022, among other items. The remainder of the project costs will be recovered as part of the 2023 subsequent year adjustment. The Settlement Agreement also includes a new charge to recover the remaining costs of the retiring Big Bend coal generation assets, Units 1 through 3, which will be spread over 15 years and will survive the termination of the Settlement Agreement. The special capital recovery schedule for all three units will be applied beginning January 1, 2022. Tampa Electric Mid-Course Adjustment to Fuel Recovery In July 2021, Tampa Electric requested a mid-course adjustment to its fuel and capacity charges, effective with September 2021 customer bills, due to an increase in fuel commodity and capacity costs in 2021. On August 3, 2021, the FPSC approved the request to recover $83 million of additional costs during the months of September through December 2021. 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 new 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. Tampa Electric submitted its storm protection plan with the FPSC on April 10, 2020. On April 27, 2020, Tampa Electric submitted a settlement agreement with the FPSC which specified a $15 million base rate reduction for SPP program costs previously recovered in base rates beginning January 1, 2021. On June 9, 2020, the FPSC approved this settlement agreement. On August 3, 2020, Tampa Electric submitted another settlement agreement to the FPSC for approval, including cost recovery of approximately $39 million in proposed storm protection project costs for 2020 and 2021. This cost recovery includes the $15 million of costs removed from base rates. This settlement agreement was approved on August 10, 2020, and Tampa Electric’s cost recovery began in January 2021. The current approved plan will apply for the years 2020, 2021 and 2022, and Tampa Electric will file a new plan in 2022 to determine cost recovery in 2023, 2024, and 2025. The June 9, 2020 settlement agreement approved by the FPSC described above also included approval of Tampa Electric’s petition to eliminate its $16 million accumulated amortization reserve surplus for intangible software assets through a credit to amortization expense in 2020. PGS Base Rates On June 8, 2020, PGS filed a petition for an increase in rates and service charges effective January 2021. On November 19, 2020, the FPSC approved a settlement agreement filed by PGS. The settlement agreement provides for an increase in base rates by $58 million annually effective January 2021, which is a $34 million increase in revenue and $24 million increase of revenues previously recovered through the cast iron and bare steel replacement rider. This settlement agreement includes an allowed regulatory ROE range of 8.90% to 11.00% with a 9.90% midpoint. It provides PGS the ability to reverse a total of $34 million of accumulated depreciation through 2023 and sets new depreciation rates effective January 1, 2021 that are consistent with PGS’s current overall average depreciation rate. Under the agreement, base rates are frozen from January 1, 2021 to December 31, 2023, unless its earned ROE were to fall below 8.90% before that time with an allowed equity in the capital structure of 54.7% from investor sources of capital. The settlement agreement further addresses tax rate changes. The agreement contains a provision whereby PGS agrees to quantify the future impact of a decrease in tax rates on net operating income through a reduction in base revenues within 120 days of when such tax change becomes law. If on the contrary, tax legislation results in a tax rate increase, PGS can establish a regulatory asset to neutralize the impact of the increase in income tax rate to be addressed in a future proceeding and with recovery beginning no sooner than January 2024 . Regulatory Assets and Liabilities Details of the regulatory assets and liabilities are presented in the following table: Regulatory Assets and Liabilities (millions) June 30, 2021 December 31, 2020 Regulatory assets: Regulatory tax asset (1) $ 98 $ 90 Cost-recovery clauses (2) 43 38 Environmental remediation (3) 25 22 Postretirement benefits (4) 298 309 Asset retirement obligation (5) 9 13 Other 8 13 Total regulatory assets 481 485 Less: Current portion 68 79 Long-term regulatory assets $ 413 $ 406 Regulatory liabilities: Regulatory tax liability (6) $ 678 $ 691 Cost-recovery clauses (2) 18 23 Accumulated reserve - cost of removal (7) 469 498 Storm reserve (8) 48 48 Other 0 1 Total regulatory liabilities 1,213 1,261 Less: Current portion 57 67 Long-term regulatory liabilities $ 1,156 $ 1,194 (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. The regulatory tax asset balance reflects the impact of the federal tax rate reduction. (2) These assets and liabilities are related to FPSC clauses and riders. 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 costs associated with environmental remediation primarily at MGP sites. The balance is included in rate base, partially offsetting the related liability, and earns a rate of return as permitted by the FPSC. The timing of recovery is based on a settlement agreement approved by the FPSC. (4) 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. (5) 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. (6) 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 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. (7) 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. (8) 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. In 2019, Tampa Electric incurred storm restoration preparation costs for Hurricane Dorian of approximately $8 million, which was charged to the storm reserve regulatory liability.

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	4. Income Taxes CARES Act On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security (CARES) Act was signed into law. The CARES Act includes several business provisions including deferral in employer payroll taxes and an employee retention payroll tax credit. On December 27, 2020, the Consolidated Appropriations Act, 2021 (the 2021 Act) was signed into law. The 2021 Act provides for modifications and expansion of the employee retention payroll tax credit enacted under the CARES Act. These Acts did not have a material impact to TEC’s financial statements. American Rescue Plan Act of 2021 On March 11, 2021, the American Rescue Plan Act of 2021 (the Act) was signed into law. The Act includes an extension of the employee retention credit through December 31, 2021. The Act did not have a material impact to TEC’s financial statements. 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 reflected in common stock. TEC’s effective tax rates for the six months ended June 30, 2021 and 2020 were 16.1% and 17.1%, respectively. The June 30, 2021 and 2020 effective tax rates are an estimate of the annual effective income tax rate. TEC’s effective tax rate for the six months ended June 30, 2021 and 2020 differed from the statutory rate principally due to the amortization of the regulatory tax liability resulting from tax reform. See Note 3 Unrecognized Tax Benefits As of June 30, 2021 and December 31, 2020, the amount of unrecognized tax benefits was $5 million and $9 million, respectively, all of which was recorded as a reduction of deferred income tax assets for tax credit carryforwards. TEC’s unrecognized federal tax benefits decreased in the first quarter of 2021 by approximately $5 million due to the settlement of its 2016 federal IRS Appeals R&D tax credits issue. TEC had $5 million and $9 million of unrecognized tax benefits at June 30, 2021 and December 31, 2020, that, if recognized, would reduce TEC’s effective tax rate.

Employee Postretirement Benefit

Employee Postretirement Benefits	6 Months Ended
	Jun. 30, 2021
Compensation And Retirement Disclosure [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 June 30, 2021 2020 2021 2020 Components of net periodic benefit cost Service cost $ 6 $ 5 $ 1 $ 0 Interest cost 6 6 2 2 Expected return on assets (13 ) (12 ) 0 0 Amortization of: Actuarial loss (gain) 5 5 (1 ) 0 Net periodic benefit cost $ 4 $ 4 $ 2 $ 2 Six months ended June 30, Components of net periodic benefit cost Service cost $ 11 $ 10 $ 1 $ 0 Interest cost 11 13 3 3 Expected return on assets (26 ) (25 ) 0 0 Amortization of: Actuarial loss (gain) 11 10 0 0 Settlement cost 0 0 0 0 Net periodic benefit cost $ 7 $ 8 $ 4 $ 3 TEC’s portion of the net periodic benefit cost for the three months ended June 30, 2021 and 2020, respectively, was $2 million and $3 million for pension benefits, and $3 million and $1 million for other postretirement benefits. TEC’s portion of the net periodic benefit cost for the six months ended June 30, 2021 and 2020, respectively, was $5 million and $6 million for pension benefits, and $5 million and $3 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 6.70% and a discount rate of 2.38% for pension benefits under its qualified pension plan for 2021. For TECO Energy’s other postretirement benefits, TECO Energy used a discount rate of 2.47% for 2021. TECO Energy made contributions of $11 million and $10 million to its qualified pension plan in each of the six months ended June 30, 2021 and 2020, respectively. TEC’s portion of these contributions was $9 million and $8 million, respectively. TECO Energy expects to make contributions to the pension plan of $10 million for the remainder of 2021. TEC estimates its portion of the remaining 2021 contribution to be $8 million. Included in the benefit cost discussed above, for the three and six months ended June 30, 2021, $5 million and $11 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 $4 million and $9 million for the three and six months ended June 30, 2020, respectively.

Short-Term Debt

Short-Term Debt	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Short-Term Debt	6. Short-Term Debt Details of TEC’s short-term borrowings are presented in the following table: June 30, 2021 December 31, 2020 Borrowings Borrowings Letters Letters Credit Outstanding - Outstanding - of Credit Credit Borrowings of Credit (millions) Facilities Credit Facilities (1) Commercial Paper (1) Outstanding Facilities Outstanding (1) Outstanding 5-year facility (2) $ 800 0 $ 410 $ 1 $ 800 $ 345 $ 1 3-year accounts receivable facility (3) 0 0 0 0 150 130 0 1-year term facility (4) 0 0 0 0 300 300 0 Total $ 800 0 $ 410 $ 1 $ 1,250 $ 775 $ 1 (1) Borrowings outstanding are reported as notes payable. (2) This 5-year facility matures March 22, 2023. 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 3-year facility matured on March 22, 2021. (4) This 1-year term facility was terminated on March 23, 2021. At June 30, 2021, the credit facility required a commitment fee of 12.5 basis points. The weighted-average interest rate on outstanding amounts payable under the credit facilities and commercial paper program at June 30, 2021 and December 31, 2020 was 0.25% and 0.89%, respectively. Commercial Paper Program On May 25, 2021, TEC established a commercial paper program (the Program) under which TEC may issue on a private placement basis unsecured commercial paper notes (the Notes). Amounts available under the Program may be borrowed, repaid and reborrowed with the aggregate amount of the Notes outstanding under the Program at any time not to exceed $800 million. must have credit facilities in place, at least equal to the amount of its commercial paper program. TEC does not issue commercial paper in an aggregate amount exceeding the then available capacity under its credit facility. Accounts Receivable Facility On July 14, 2020 and October 30, 2020, TEC amended its $150 million accounts receivable collateralized borrowing facility (Loan Agreement) in order to change certain performance ratios. The amended Loan Agreement was effective as of June 30, 2020 and September 30, 2020. On March 22, 2021, this agreement matured and terminated. Non Revolving Term Loan On February 6, 2020, TEC entered into a 364-day, $300 million credit agreement with a group of banks. The credit agreement had a maturity date of February 4, 2021; contained customary representations and warranties, events of default, and financial and other covenants; and provided for interest to accrue at variable rates based on either the London interbank deposit rate, Wells Fargo Bank’s prime rate, or the federal funds rate, plus a margin. On January 29, 2021, TEC extended the maturity date of the agreement to April 29, 2021. On March 23, 2021, this loan was repaid and terminated. 5-Year Credit Facility On December 18, 2020, TEC amended and restated its bank credit facility, entering into a Sixth Amended and Restated Credit Agreement. The amendment extended the maturity date of the credit facility from March 22, 2022 to March 22, 2023 (subject to further extension with the consent of each lender); increased the amount of the commitment by the lenders to $800 million; and provided for an interest rate based on either the London interbank deposit rate, Wells Fargo Bank’s prime rate, or the federal funds rate, plus a margin; allows TEC to borrow funds on a same-day basis under a swingline loan provision, which loans mature on the fourth banking day after which any such loans are made and bear interest at an interest rate as agreed by the borrower and the relevant swingline lender prior to the making of any such loans; continues to allow TEC to request the lenders to increase their commitments under the credit facility by up to $100 million in the aggregate; includes a $80 million letter of credit facility; and made other technical changes.

Long-Term Debt

Long-Term Debt	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Long-Term Debt	7. Long-Term Debt Fair Value of Long-Term Debt At June 30, 2021, TEC’s long-term debt, including the current portion, had a carrying amount of $3,385 million and an estimated fair market value of $4,035 million. At December 31, 2020, TEC’s total long-term debt, including the current portion, had a carrying amount of $2,872 million and an estimated fair market value of $3,597 million. The fair value of the debt securities is determined using Level 2 measurements Note 11 Tampa Electric Company 2.40% Notes due 2031 and 3.45% Notes due 2051 On March 18, 2021, TEC completed a sale of (i) $400 million aggregate principal amount of 2.40% Notes due March 15, 2031 (the 2031 Notes) and (ii) $400 million aggregate principal amount of 3.45% Notes due March 15, 2051 (the 2051 Notes, and collectively, the Notes). Until December 15, 2030, in the case of the 2031 Notes, or September 15, 2050, in the case of the 2051 Notes, TEC may redeem all or any part of such series of Notes at its option at a redemption price equal to the greater of (i) 100% of the principal amount of such series of Notes to be redeemed or (ii) the sum of the present values of the remaining payments of principal and interest on the Notes to be redeemed that would be due if the Notes matured on (a) December 15, 2030, in the case of the 2031 Notes, discounted to the redemption date on a semiannual basis at the applicable treasury rate (as defined in the Indenture), plus 15 basis points, or (b) September 15, 2050, in the case of the 2051 Notes, discounted to the redemption date on a semiannual basis at the applicable treasury rate, plus 20 basis points; in either case, the redemption price would include accrued and unpaid interest to the redemption date. At any time on or after December 15, 2030, in the case of the 2031 Notes or September 15, 2050, in the case of the 2051 Notes, TEC may, at its option, redeem such series of the Notes, in whole or in part, at 100% of the principal amount of such series of the Notes being redeemed plus accrued and unpaid interest thereon to, but excluding, the date of redemption.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2021
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 TEC, through its Tampa Electric and PGS divisions, is a PRP for certain superfund sites and, through its PGS division, for certain former MGP sites. While the joint and several liability associated with these sites presents the potential for significant response costs, as of June 30, 2021 and December 31, 2020, TEC has estimated its ultimate financial liability to be $ 17 million The estimated amounts represent only the portion of the cleanup costs attributable to TEC. The estimates to perform the work are based on TEC’s experience with similar work, adjusted for site-specific conditions and agreements with the respective governmental agencies. The estimates are made in current dollars, are not discounted and do not assume any insurance recoveries. In instances where other PRPs are involved, most of those PRPs are creditworthy and are likely to continue to be creditworthy for the duration of the remediation work. However, in those instances that they are not, TEC could be liable for more than TEC’s currently assessed percentage of the remediation costs. Factors that could impact these estimates include the ability of other PRPs to pay their pro-rata portion of the cleanup costs, additional testing and investigation which could expand the scope of the cleanup activities, additional liability that might arise from the cleanup activities themselves or changes in laws or regulations that could require additional remediation. Under current regulations, these costs are recoverable through customer rates established in subsequent base rate proceedings. See Note 3 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 June 30, 2021: Long-term Demand Purchased Capital Fuel and Service Operating Side (millions) Power Transportation Projects Gas Supply Agreements Leases Management Total 2021 $ 35 $ 119 $ 297 $ 173 $ 35 $ 2 $ 2 $ 663 2022 0 232 84 52 32 3 3 406 2023 0 211 58 1 43 3 0 316 2024 0 205 0 0 26 3 0 234 2025 0 191 0 0 18 2 0 211 Thereafter 0 2,014 0 0 66 48 0 2,128 Total future minimum payments $ 35 $ 2,972 $ 439 $ 226 $ 220 $ 61 $ 5 $ 3,958 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 June 30, 2021, TEC was in compliance with all required covenants.

Segment Information

Segment Information	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Segment Information	9. Segment Information (millions) Tampa Tampa Electric Three months ended June 30, Electric PGS Eliminations Company 2021 Revenues - external $ 531 $ 123 $ 0 $ 654 Intracompany sales 1 0 (1 ) 0 Total revenues 532 123 (1 ) 654 Total interest charges 29 5 0 34 Net income $ 102 $ 19 $ 0 $ 121 2020 Revenues - external $ 453 $ 96 $ 0 $ 549 Intracompany sales 1 1 (2 ) 0 Total revenues 454 97 (2 ) 549 Total interest charges 28 4 0 32 Net income $ 106 $ 11 $ 0 $ 117 Six months ended June 30, 2021 Revenues - external $ 977 $ 276 $ 0 $ 1,253 Intracompany sales 2 2 (4 ) 0 Total revenues 979 278 (4 ) 1,253 Total interest charges 57 10 0 67 Net income $ 167 $ 46 $ 0 $ 213 2020 Revenues - external $ 873 $ 223 $ 0 $ 1,096 Intracompany sales 2 4 (6 ) 0 Total revenues 875 227 (6 ) 1,096 Total interest charges 58 8 0 66 Net income $ 165 $ 29 $ 0 $ 194 Total assets at June 30, 2021 $ 10,101 $ 2,021 $ (663 ) (1) $ 11,459 Total assets at December 31, 2020 $ 9,800 $ 1,901 $ (653 ) (1) $ 11,048 (1) Amounts primarily relate to consolidated deferred tax reclassifications. Deferred tax assets are reclassified and netted with deferred tax liabilities upon consolidation.

Revenue

Revenue	6 Months Ended
	Jun. 30, 2021
Revenues [Abstract]
Revenue	10. Revenue The following disaggregates TEC’s revenue by major source: (millions) Tampa Tampa Electric Three months ended June 30, 2021 Electric PGS Eliminations Company Electric revenue Residential $ 276 $ 0 $ 0 $ 276 Commercial 144 0 0 144 Industrial 41 0 0 41 Regulatory deferrals and unbilled revenue 11 0 0 11 Other (1) 60 0 (1 ) 59 Total electric revenue 532 0 (1 ) 531 Gas revenue Residential 0 49 0 49 Commercial 0 46 0 46 Industrial (2) 0 6 0 6 Other (3) 0 22 0 22 Total gas revenue 0 123 0 123 Total revenue $ 532 $ 123 $ (1 ) $ 654 Three months ended June 30, 2020 Electric revenue Residential $ 254 $ 0 $ 0 $ 254 Commercial 121 0 0 121 Industrial 32 0 0 32 Regulatory deferrals and unbilled revenue (3 ) 0 0 (3 ) Other (1) 50 ` 0 (1 ) 49 Total electric revenue 454 0 (1 ) 453 Gas revenue Residential 0 36 0 36 Commercial 0 28 0 28 Industrial (2) 0 5 0 5 Other (3) 0 28 (1 ) 27 Total gas revenue 0 97 (1 ) 96 Total revenue $ 454 $ 97 $ (2 ) $ 549 (millions) Tampa Tampa Electric Six months ended June 30, 2021 Electric PGS Eliminations Company Electric revenue Residential $ 508 $ 0 $ 0 $ 508 Commercial 270 0 0 270 Industrial 78 0 0 78 Regulatory deferrals and unbilled revenue 9 0 0 9 Other (1) 114 0 (2 ) 112 Total electric revenue 979 0 (2 ) 977 Gas revenue Residential 0 116 0 116 Commercial 0 99 0 99 Industrial (2) 0 12 0 12 Other (3) 0 51 (2 ) 49 Total gas revenue 0 278 (2 ) 276 Total revenue $ 979 $ 278 $ (4 ) $ 1,253 Six months ended June 30, 2020 Electric revenue Residential $ 459 $ 0 $ 0 $ 459 Commercial 246 0 0 246 Industrial 69 0 0 69 Regulatory deferrals and unbilled revenue (5 ) 0 0 (5 ) Other (1) 106 0 (2 ) 104 Total electric revenue 875 0 (2 ) 873 Gas revenue Residential 0 84 0 84 Commercial 0 69 0 69 Industrial (2) 0 11 0 11 Other (3) 0 63 (4 ) 59 Total gas revenue 0 227 (4 ) 223 Total revenue $ 875 $ 227 $ (6 ) $ 1,096 (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 June 30, 2021 and December 31, 2020, the aggregate amount of the transaction price allocated to remaining performance obligations was approximately $130 million and $135 million, respectively. 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 2033.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2021
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 June 30, 2021 and December 31, 2020, 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

Subsequent Events

Subsequent Events	6 Months Ended
	Jun. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	12. Subsequent Events On August 6, 2021, TEC filed with the FPSC a joint motion for approval of a settlement agreement dated as of August 6, 2021 by and among TEC and the intervenors in TEC’s rate case filed with the FPSC in April 2021. In addition, on August 3, 2021, the FPSC approved Tampa Electric’s request for a mid-course adjustment to its fuel and capacity charges, effective with September 2021 customer bills. See Note 3 – Tampa Electric Base Rates, Tampa Electric Big Bend Modernization Project Tampa Electric Mid-Course Adjustment to Fuel Recovery

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2021
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 the natural gas division, referred to as PGS. Intercompany balances and transactions within the divisions have been eliminated in consolidation. 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 June 30, 2021 and December 31, 2020, and the results of operations and cash flows for the periods ended June 30, 2021 and 2020. The results of operations for the three and six months ended June 30, 2021 are not necessarily indicative of the results that can be expected for the entire fiscal year ending December 31, 2021. 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. Since 2020, the outbreak of COVID-19 has resulted in governments worldwide enacting emergency measures to combat the spread of the virus. While management considered the impact of the COVID-19 pandemic in TEC’s estimates and results, the financial statements as of June 30, 2021 and December 31, 2020 and for the three and six months ended June 30, 2021 and 2020 were not materially impacted by the COVID-19 pandemic.
Receivables and Allowance for Credit Losses	Receivables and Allowance for Credit Losses Receivables from contracts with customers, which consist of services to residential, commercial, industrial and other customers, were $258 million and $214 million as of June 30, 2021 and December 31, 2020, 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 Tampa Electric’s and PGS’s estimates of credit losses include, but are not limited to, customer credit issues, generating fuel prices, customer deposits and general economic conditions, including the impacts of the COVID-19 pandemic. Accounts are reserved in the allowance or written off once they are deemed to be uncollectible. As of June 30, 2021 and December 31, 2020, unbilled revenues of $83 million and $73 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 Tampa Electric and PGS are 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 Tampa Electric and PGS are included as an expense on the Consolidated Condensed Statements of Income in “Taxes, other than income”. These amounts totaled $31 million and $26 million for the three months ended June 30, 2021 and 2020, respectively, and totaled $60 million and $53 million for the six months ended June 30, 2021 and 2020, respectively.

Regulatory (Tables)

Regulatory (Tables)	6 Months Ended
	Jun. 30, 2021
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) June 30, 2021 December 31, 2020 Regulatory assets: Regulatory tax asset (1) $ 98 $ 90 Cost-recovery clauses (2) 43 38 Environmental remediation (3) 25 22 Postretirement benefits (4) 298 309 Asset retirement obligation (5) 9 13 Other 8 13 Total regulatory assets 481 485 Less: Current portion 68 79 Long-term regulatory assets $ 413 $ 406 Regulatory liabilities: Regulatory tax liability (6) $ 678 $ 691 Cost-recovery clauses (2) 18 23 Accumulated reserve - cost of removal (7) 469 498 Storm reserve (8) 48 48 Other 0 1 Total regulatory liabilities 1,213 1,261 Less: Current portion 57 67 Long-term regulatory liabilities $ 1,156 $ 1,194 (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. The regulatory tax asset balance reflects the impact of the federal tax rate reduction. (2) These assets and liabilities are related to FPSC clauses and riders. 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 costs associated with environmental remediation primarily at MGP sites. The balance is included in rate base, partially offsetting the related liability, and earns a rate of return as permitted by the FPSC. The timing of recovery is based on a settlement agreement approved by the FPSC. (4) 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. (5) 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. (6) 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 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. (7) 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. (8) 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. In 2019, Tampa Electric incurred storm restoration preparation costs for Hurricane Dorian of approximately $8 million, which was charged to the storm reserve regulatory liability.

Employee Postretirement Benef_2

Employee Postretirement Benefits (Tables)	6 Months Ended
	Jun. 30, 2021
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 June 30, 2021 2020 2021 2020 Components of net periodic benefit cost Service cost $ 6 $ 5 $ 1 $ 0 Interest cost 6 6 2 2 Expected return on assets (13 ) (12 ) 0 0 Amortization of: Actuarial loss (gain) 5 5 (1 ) 0 Net periodic benefit cost $ 4 $ 4 $ 2 $ 2 Six months ended June 30, Components of net periodic benefit cost Service cost $ 11 $ 10 $ 1 $ 0 Interest cost 11 13 3 3 Expected return on assets (26 ) (25 ) 0 0 Amortization of: Actuarial loss (gain) 11 10 0 0 Settlement cost 0 0 0 0 Net periodic benefit cost $ 7 $ 8 $ 4 $ 3

Short-Term Debt (Tables)

Short-Term Debt (Tables)	6 Months Ended
	Jun. 30, 2021
Debt Disclosure [Abstract]
Schedule of Short-term Borrowings	Details of TEC’s short-term borrowings are presented in the following table: June 30, 2021 December 31, 2020 Borrowings Borrowings Letters Letters Credit Outstanding - Outstanding - of Credit Credit Borrowings of Credit (millions) Facilities Credit Facilities (1) Commercial Paper (1) Outstanding Facilities Outstanding (1) Outstanding 5-year facility (2) $ 800 0 $ 410 $ 1 $ 800 $ 345 $ 1 3-year accounts receivable facility (3) 0 0 0 0 150 130 0 1-year term facility (4) 0 0 0 0 300 300 0 Total $ 800 0 $ 410 $ 1 $ 1,250 $ 775 $ 1 (1) Borrowings outstanding are reported as notes payable. (2) This 5-year facility matures March 22, 2023. 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 3-year facility matured on March 22, 2021. (4) This 1-year term facility was terminated on March 23, 2021.

Commitments and Contingencies (

Commitments and Contingencies (Tables)	6 Months Ended
	Jun. 30, 2021
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 June 30, 2021: Long-term Demand Purchased Capital Fuel and Service Operating Side (millions) Power Transportation Projects Gas Supply Agreements Leases Management Total 2021 $ 35 $ 119 $ 297 $ 173 $ 35 $ 2 $ 2 $ 663 2022 0 232 84 52 32 3 3 406 2023 0 211 58 1 43 3 0 316 2024 0 205 0 0 26 3 0 234 2025 0 191 0 0 18 2 0 211 Thereafter 0 2,014 0 0 66 48 0 2,128 Total future minimum payments $ 35 $ 2,972 $ 439 $ 226 $ 220 $ 61 $ 5 $ 3,958

Segment Information (Tables)

Segment Information (Tables)	6 Months Ended
	Jun. 30, 2021
Segment Reporting [Abstract]
Schedule of Segment Information	(millions) Tampa Tampa Electric Three months ended June 30, Electric PGS Eliminations Company 2021 Revenues - external $ 531 $ 123 $ 0 $ 654 Intracompany sales 1 0 (1 ) 0 Total revenues 532 123 (1 ) 654 Total interest charges 29 5 0 34 Net income $ 102 $ 19 $ 0 $ 121 2020 Revenues - external $ 453 $ 96 $ 0 $ 549 Intracompany sales 1 1 (2 ) 0 Total revenues 454 97 (2 ) 549 Total interest charges 28 4 0 32 Net income $ 106 $ 11 $ 0 $ 117 Six months ended June 30, 2021 Revenues - external $ 977 $ 276 $ 0 $ 1,253 Intracompany sales 2 2 (4 ) 0 Total revenues 979 278 (4 ) 1,253 Total interest charges 57 10 0 67 Net income $ 167 $ 46 $ 0 $ 213 2020 Revenues - external $ 873 $ 223 $ 0 $ 1,096 Intracompany sales 2 4 (6 ) 0 Total revenues 875 227 (6 ) 1,096 Total interest charges 58 8 0 66 Net income $ 165 $ 29 $ 0 $ 194 Total assets at June 30, 2021 $ 10,101 $ 2,021 $ (663 ) (1) $ 11,459 Total assets at December 31, 2020 $ 9,800 $ 1,901 $ (653 ) (1) $ 11,048 (1) Amounts primarily relate to consolidated deferred tax reclassifications. Deferred tax assets are reclassified and netted with deferred tax liabilities upon consolidation.

Revenue (Tables)

Revenue (Tables)	6 Months Ended
	Jun. 30, 2021
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 June 30, 2021 Electric PGS Eliminations Company Electric revenue Residential $ 276 $ 0 $ 0 $ 276 Commercial 144 0 0 144 Industrial 41 0 0 41 Regulatory deferrals and unbilled revenue 11 0 0 11 Other (1) 60 0 (1 ) 59 Total electric revenue 532 0 (1 ) 531 Gas revenue Residential 0 49 0 49 Commercial 0 46 0 46 Industrial (2) 0 6 0 6 Other (3) 0 22 0 22 Total gas revenue 0 123 0 123 Total revenue $ 532 $ 123 $ (1 ) $ 654 Three months ended June 30, 2020 Electric revenue Residential $ 254 $ 0 $ 0 $ 254 Commercial 121 0 0 121 Industrial 32 0 0 32 Regulatory deferrals and unbilled revenue (3 ) 0 0 (3 ) Other (1) 50 ` 0 (1 ) 49 Total electric revenue 454 0 (1 ) 453 Gas revenue Residential 0 36 0 36 Commercial 0 28 0 28 Industrial (2) 0 5 0 5 Other (3) 0 28 (1 ) 27 Total gas revenue 0 97 (1 ) 96 Total revenue $ 454 $ 97 $ (2 ) $ 549 (millions) Tampa Tampa Electric Six months ended June 30, 2021 Electric PGS Eliminations Company Electric revenue Residential $ 508 $ 0 $ 0 $ 508 Commercial 270 0 0 270 Industrial 78 0 0 78 Regulatory deferrals and unbilled revenue 9 0 0 9 Other (1) 114 0 (2 ) 112 Total electric revenue 979 0 (2 ) 977 Gas revenue Residential 0 116 0 116 Commercial 0 99 0 99 Industrial (2) 0 12 0 12 Other (3) 0 51 (2 ) 49 Total gas revenue 0 278 (2 ) 276 Total revenue $ 979 $ 278 $ (4 ) $ 1,253 Six months ended June 30, 2020 Electric revenue Residential $ 459 $ 0 $ 0 $ 459 Commercial 246 0 0 246 Industrial 69 0 0 69 Regulatory deferrals and unbilled revenue (5 ) 0 0 (5 ) Other (1) 106 0 (2 ) 104 Total electric revenue 875 0 (2 ) 873 Gas revenue Residential 0 84 0 84 Commercial 0 69 0 69 Industrial (2) 0 11 0 11 Other (3) 0 63 (4 ) 59 Total gas revenue 0 227 (4 ) 223 Total revenue $ 875 $ 227 $ (6 ) $ 1,096 (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.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Accounting Policies [Abstract]
Receivables from contracts with customers	$ 258		$ 258		$ 214
Unbilled revenues	83		83		$ 73
Franchise fees and gross receipts taxes	$ 31	$ 26	$ 60	$ 53

Regulatory - Additional Informa

Regulatory - Additional Information (Detail)

Aug. 06, 2021USD ($)

Aug. 03, 2021USD ($)

Nov. 19, 2020USD ($)

Aug. 18, 2020USD ($)

Aug. 03, 2020USD ($)

Apr. 27, 2020USD ($)

Jun. 28, 2019USD ($)MW

Jun. 29, 2018USD ($)MW

Dec. 12, 2017USD ($)MW

Sep. 27, 2017USD ($)MW

Jan. 31, 2024USD ($)

Jan. 31, 2023USD ($)

Jun. 30, 2021USD ($)Unit

Dec. 31, 2020USD ($)

Jun. 09, 2020USD ($)

Public Utilities General Disclosures [Line Items]

Utility plant, at original costs

$ 14,346,000,000

$ 13,818,000,000

Accumulated depreciation

$ 3,897,000,000

3,712,000,000

Number of units applied for recovery | Unit

3

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

$ 11,876,000,000

11,486,000,000

Peoples Gas System [Member]

Public Utilities General Disclosures [Line Items]

Increase in revenue

$ 34,000,000

Allowed equity in the capital structure

54.70%

Impact of tax reform through reduction in base revenue days

120 days

Accumulated depreciation

$ 34,000,000

Increase in annual base rate

58,000,000

Peoples Gas System [Member] | Cast Iron and Bare Steel Replacement Rider [Member]

Public Utilities General Disclosures [Line Items]

Increase in revenue

$ 24,000,000

Subsequent Event [Member]

Public Utilities General Disclosures [Line Items]

Additional cost recovery from settlement agreement

$ 83,000,000

Settlement Agreement [Member] | Subsequent Event [Member]

Public Utilities General Disclosures [Line Items]

Settlement agreement, approval date

Aug. 6, 2021

Base rate adjustment amount

$ 123,000,000

Increase in revenue

$ 191,000,000

Settlement agreement number of subsequent years adjustments

2 years

Allowed equity in the capital structure

54.00%

Basis point increase applicable

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

$ 90,000,000

Settlement Agreement [Member] | US Treasury Bond [Member] | Subsequent Event [Member]

Public Utilities General Disclosures [Line Items]

Calculating period

30 years

Determining period

6 months

Minimum [Member] | Peoples Gas System [Member]

Public Utilities General Disclosures [Line Items]

Percentage of ROE

8.90%

Base rate agreement frozen period

Jan. 1, 2021

Minimum [Member] | Settlement Agreement [Member] | Subsequent Event [Member]

Public Utilities General Disclosures [Line Items]

Percentage of ROE

9.00%

Base rate agreement frozen period

Jan. 1, 2022

Minimum [Member] | Settlement Agreement [Member] | US Treasury Bond [Member] | Subsequent Event [Member]

Public Utilities General Disclosures [Line Items]

ROE revenue basis point on yield rate

0.50%

Maximum [Member] | Peoples Gas System [Member]

Public Utilities General Disclosures [Line Items]

Percentage of ROE

11.00%

Base rate agreement frozen period

Dec. 31, 2023

Maximum [Member] | Settlement Agreement [Member] | Subsequent Event [Member]

Public Utilities General Disclosures [Line Items]

Percentage of ROE

11.00%

Base rate agreement frozen period

Dec. 31, 2024

Mid Point [Member] | Peoples Gas System [Member]

Public Utilities General Disclosures [Line Items]

Percentage of ROE

9.90%

Mid Point [Member] | Settlement Agreement [Member] | Subsequent Event [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 December 31, 2021

Settlement agreement, approval date

Nov. 6, 2017

Solar energy capacity | MW

600

Solar generation capacity investments

$ 850,000,000

Solar Project Cost Recovery [Member] | Solar Base Rate Adjustments [Member]

Public Utilities General Disclosures [Line Items]

True-up amount returned to customers

$ 5,000,000

Estimated true-up amount returned to customers

4,000,000

Solar Project Cost Recovery [Member] | Effective September 1, 2018 [Member]

Public Utilities General Disclosures [Line Items]

Solar energy capacity | MW

145

Estimated annual revenue requirements

$ 24,000,000

Solar Project Cost Recovery [Member] | Effective January 1, 2019 [Member]

Public Utilities General Disclosures [Line Items]

Solar energy capacity | MW

260

Estimated annual revenue requirements

$ 46,000,000

Solar Project Cost Recovery [Member] | Effective January 1, 2020 [Member]

Public Utilities General Disclosures [Line Items]

Solar energy capacity | MW

149

Estimated annual revenue requirements

$ 26,000,000

Solar Project Cost Recovery [Member] | Effective January 1, 2021 [Member]

Public Utilities General Disclosures [Line Items]

Solar energy capacity | MW

46

Estimated annual 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] | Subsequent Event [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] | Subsequent Event [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

850,000,000

Investments in energy projects till date

611,000,000

Accumulated depreciation

$ 91,000,000

88,000,000

Settlement agreement recovery description

Tampa Electric’s Settlement Agreement provides recovery for the Big Bend Modernization project in two phases. The first phase is a revenue increase to cover the costs of the assets in service during 2022, among other items. The remainder of the project costs will be recovered as part of the 2023 subsequent year adjustment.

Big Bend Modernization Project [Member] | Electric Utility Plant [Member]

Public Utilities General Disclosures [Line Items]

Utility plant, at original costs

$ 200,000,000

$ 200,000,000

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

2023

Big Bend Coal Generation Assets [Member]

Public Utilities General Disclosures [Line Items]

Settlement agreement cost recovery period

15 years

Storm Protection Plan [Member]

Public Utilities General Disclosures [Line Items]

Cost recovery from settlement agreement

$ 39,000,000

Reduction in annual base rates

$ 15,000,000

Regulatory - Schedule of Regula

Regulatory - Schedule of Regulatory Assets and Regulatory Liabilities (Detail) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Regulatory assets:
Regulatory assets	$ 481	$ 485
Less: Current portion	68	79
Long-term regulatory assets	413	406
Regulatory liabilities:
Regulatory liabilities	1,213	1,261
Less: Current portion	57	67
Long-term regulatory liabilities	1,156	1,194
Regulatory Tax Asset [Member]
Regulatory assets:
Regulatory assets	98	90
Cost-Recovery Clauses [Member]
Regulatory assets:
Regulatory assets	43	38
Environmental Remediation [Member]
Regulatory assets:
Regulatory assets	25	22
Postretirement Benefits [Member]
Regulatory assets:
Regulatory assets	298	309
Asset Retirement Obligation [Member]
Regulatory assets:
Regulatory assets	9	13
Other [Member]
Regulatory assets:
Regulatory assets	8	13
Regulatory Tax Liability [Member] | Non-Current Liabilities [Member]
Regulatory liabilities:
Regulatory liabilities	678	691
Cost-Recovery Clauses [Member]
Regulatory liabilities:
Regulatory liabilities	18	23
Storm Reserve [Member]
Regulatory liabilities:
Regulatory liabilities	48	48
Accumulated Reserve - Cost of Removal [Member]
Regulatory liabilities:
Regulatory liabilities	469	498
Other [Member]
Regulatory liabilities:
Regulatory liabilities	$ 0	$ 1

Regulatory - Schedule of Regu_2

Regulatory - Schedule of Regulatory Assets and Regulatory Liabilities (Parenthetical) (Detail) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2019	Oct. 31, 2013
Storm Restoration Cost Recovery [Member]
Schedule Of Regulatory Assets And Liabilities [Line Items]
Minimum cost recovery period	12 months
Replenishment reserve for recovery of cost			$ 56
Hurricane Dorian [Member]
Schedule Of Regulatory Assets And Liabilities [Line Items]
Storm restoration preparation costs		$ 8

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2021	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Income Taxes [Line Items]
Unrecognized tax benefits		$ 5		$ 9
Unrecognized tax benefit that would reduce effective tax rate		$ 5		$ 9
Federal [Member] | R&D Tax Credits [Member]
Income Taxes [Line Items]
Unrecognized tax benefits decreased	$ 5
Tampa Electric [Member]
Income Taxes [Line Items]
Effective tax rate		16.10%	17.10%

Employee Postretirement Benef_3

Employee Postretirement Benefits - Schedule of Net Periodic Benefit Cost (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Pension Benefits [Member]
Amortization of:
Net periodic benefit cost	$ 2	$ 3	$ 5	$ 6
Other Postretirement Benefits [Member]
Amortization of:
Net periodic benefit cost	3	1	5	3
TECO Energy [Member] | Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	6	5	11	10
Interest cost	6	6	11	13
Expected return on assets	(13)	(12)	(26)	(25)
Amortization of:
Actuarial loss (gain)	5	5	11	10
Settlement cost			0	0
Net periodic benefit cost	4	4	7	8
TECO Energy [Member] | Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	0	1	0
Interest cost	2	2	3	3
Expected return on assets	0	0	0	0
Amortization of:
Actuarial loss (gain)	(1)	0	0	0
Settlement cost			0	0
Net periodic benefit cost	$ 2	$ 2	$ 4	$ 3

Employee Postretirement Benef_4

Employee Postretirement Benefits - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Reclassification of regulatory assets to net income as part of periodic benefit cost	$ 5	$ 4	$ 11	$ 9
TECO Energy [Member]
Defined Benefit Plan Disclosure [Line Items]
Long-term EROA			6.70%
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	2	3	$ 5	6
Employer contributions			9	8
Employer contributions in remainder of year	8		8
Pension Benefits [Member] | TECO Energy [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	4	4	$ 7	8
Discount rate			2.38%
Employer contributions			$ 11	10
Employer contributions in remainder of year	10		10
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	3	1	5	3
Other Postretirement Benefits [Member] | TECO Energy [Member]
Defined Benefit Plan Disclosure [Line Items]
Net periodic benefit cost	$ 2	$ 2	$ 4	$ 3
Discount rate			2.47%

Short-Term Debt - Schedule of S

Short-Term Debt - Schedule of Short-Term Borrowings (Detail) - USD ($)	Jun. 30, 2021	Dec. 31, 2020	Dec. 18, 2020	Oct. 30, 2020	Jul. 14, 2020
Line Of Credit Facility [Line Items]
Credit Facilities	$ 800,000,000	$ 1,250,000,000	$ 80,000,000
Borrowings Outstanding	410,000,000	775,000,000
Letters of Credit Outstanding	1,000,000	1,000,000
Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	0
Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	410,000,000
5-year Facility [Member]
Line Of Credit Facility [Line Items]
Credit Facilities	800,000,000	800,000,000
Borrowings Outstanding		345,000,000
Letters of Credit Outstanding	1,000,000	1,000,000
5-year Facility [Member] | Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	0
5-year Facility [Member] | Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	410,000,000
1-year Term Facility [Member]
Line Of Credit Facility [Line Items]
Credit Facilities	0	300,000,000
Borrowings Outstanding		300,000,000
Letters of Credit Outstanding	0	0
1-year Term Facility [Member] | Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	0
1-year Term Facility [Member] | Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	0
3-year Accounts Receivable Facility [Member]
Line Of Credit Facility [Line Items]
Credit Facilities	0	150,000,000		$ 150,000,000	$ 150,000,000
Borrowings Outstanding		130,000,000
Letters of Credit Outstanding	0	$ 0
3-year Accounts Receivable Facility [Member] | Credit Facilities [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	0
3-year Accounts Receivable Facility [Member] | Commercial Paper [Member]
Line Of Credit Facility [Line Items]
Borrowings Outstanding	$ 0

Short-Term Debt - Schedule of_2

Short-Term Debt - Schedule of Short-Term Borrowings (Parenthetical) (Detail) - USD ($)	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020	May 25, 2021
5-year Facility [Member]
Line Of Credit Facility [Line Items]
Credit facility maturity date	Mar. 22, 2023	Mar. 22, 2023
3-year Accounts Receivable Facility [Member]
Line Of Credit Facility [Line Items]
Credit facility maturity date	Mar. 22, 2021	Mar. 22, 2021
1-year Term Facility [Member]
Line Of Credit Facility [Line Items]
Credit facility maturity date	Mar. 23, 2021	Mar. 23, 2021
Maximum [Member] | Commercial Paper Program [Member]
Line Of Credit Facility [Line Items]
Commercial paper issued	$ 800,000,000		$ 800,000,000

Short-Term Debt - Additional In

Short-Term Debt - Additional Information (Detail) - USD ($)	Jan. 29, 2021	Dec. 18, 2020	Oct. 30, 2020	Jul. 14, 2020	Feb. 06, 2020	Jun. 30, 2021	Dec. 31, 2020	May 25, 2021
Line Of Credit Facility [Line Items]
Commitment fees, percentage						0.125%
Weighted-average interest rate						0.25%	0.89%
Line of credit facility maximum borrowing capacity		$ 80,000,000				$ 800,000,000	$ 1,250,000,000
Lenders commitment amount		800,000,000
Increase of credit facility		$ 100,000,000
Commercial Paper Program [Member]
Line Of Credit Facility [Line Items]
Debt instrument, restrictive covenants						The maturities of the Notes will vary, but may not exceed 270 days from the date of issue.
3-year Accounts Receivable Facility [Member]
Line Of Credit Facility [Line Items]
Credit facility amendment date			Oct. 30, 2020	Jul. 14, 2020
Line of credit facility maximum borrowing capacity			$ 150,000,000	$ 150,000,000		$ 0	$ 150,000,000
Credit facility maturity date						Mar. 22, 2021	Mar. 22, 2021
364-day Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Line of credit facility maximum borrowing capacity					$ 300,000,000
Credit facility maturity period					364 days
Credit facility maturity date					Feb. 4, 2021
Credit Facility extended maturity date	Apr. 29, 2021
Maximum [Member] | Amended And Restated Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Debt instrument maturity date		Mar. 22, 2023
Maximum [Member] | Commercial Paper Program [Member]
Line Of Credit Facility [Line Items]
Commercial paper issued						$ 800,000,000		$ 800,000,000
Minimum [Member] | Amended And Restated Credit Agreement [Member]
Line Of Credit Facility [Line Items]
Debt instrument maturity date		Mar. 22, 2022

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - USD ($) $ in Millions	Mar. 18, 2021	Jun. 30, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt		$ 3,385	$ 2,872
Estimated fair value		$ 4,035	$ 3,597
2.40% Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity year	2031
Aggregate principal amount issued	$ 400
Stated interest rate	2.40%
Debt instrument maturity date	Mar. 15, 2031
Redeemable principal amount percentage	100.00%
Basis spread on federal funds rate	0.15%
Redeemable principal amount percentage	100.00%
Debt instrument, start date of redemption	Dec. 15, 2030
Debt instrument, offering date	Mar. 18, 2021
3.45% Notes [Member]
Debt Instrument [Line Items]
Debt instrument, maturity year	2051
Aggregate principal amount issued	$ 400
Stated interest rate	3.45%
Debt instrument maturity date	Mar. 15, 2051
Redeemable principal amount percentage	100.00%
Basis spread on federal funds rate	0.20%
Redeemable principal amount percentage	100.00%
Debt instrument, start date of redemption	Sep. 15, 2050
Debt instrument, offering date	Mar. 18, 2021

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
PGS [Member]
Long Term Commitments [Line Items]
Ultimate financial liability to superfund sites and former MGP sites	$ 17	$ 17

Commitments and Contingencies_2

Commitments and Contingencies - Schedule of Long-term Commitments (Detail) $ in Millions	Jun. 30, 2021USD ($)
Other Commitments [Line Items]
2021	$ 663
2022	406
2023	316
2024	234
2025	211
Thereafter	2,128
Total future minimum payments	3,958
Purchased Power [Member]
Other Commitments [Line Items]
2021	35
2022	0
2023	0
2024	0
2025	0
Thereafter	0
Total future minimum payments	35
Transportation [Member]
Other Commitments [Line Items]
2021	119
2022	232
2023	211
2024	205
2025	191
Thereafter	2,014
Total future minimum payments	2,972
Capital Projects [Member]
Other Commitments [Line Items]
2021	297
2022	84
2023	58
2024	0
2025	0
Thereafter	0
Total future minimum payments	439
Fuel and Gas Supply [Member]
Other Commitments [Line Items]
2021	173
2022	52
2023	1
2024	0
2025	0
Thereafter	0
Total future minimum payments	226
Long-term Service Agreements [Member]
Other Commitments [Line Items]
2021	35
2022	32
2023	43
2024	26
2025	18
Thereafter	66
Total future minimum payments	220
Operating Leases [Member]
Other Commitments [Line Items]
2021	2
2022	3
2023	3
2024	3
2025	2
Thereafter	48
Total future minimum payments	61
Demand Side Management [Member]
Other Commitments [Line Items]
2021	2
2022	3
2023	0
2024	0
2025	0
Thereafter	0
Total future minimum payments	$ 5

Segment Information - Schedule

Segment Information - Schedule of Segment Information (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Segment Reporting Information [Line Items]
Total revenues	$ 654	$ 549	$ 1,253	$ 1,096
Total interest charges	34	32	67	66
Net income	121	117	213	194
Total assets	11,459		11,459		$ 11,048
Revenues - External [Member]
Segment Reporting Information [Line Items]
Total revenues	654	549	1,253	1,096
Intracompany Sales [Member]
Segment Reporting Information [Line Items]
Intracompany sales	0	0	0	0
Eliminations [Member]
Segment Reporting Information [Line Items]
Total revenues	(1)	(2)	(4)	(6)
Total interest charges	0	0	0	0
Net income	0	0	0	0
Total assets	(663)		(663)		(653)
Eliminations [Member] | Revenues - External [Member]
Segment Reporting Information [Line Items]
Total revenues	0	0	0	0
Eliminations [Member] | Intracompany Sales [Member]
Segment Reporting Information [Line Items]
Intracompany sales	(1)	(2)	(4)	(6)
Tampa Electric [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	532	454	979	875
Total interest charges	29	28	57	58
Net income	102	106	167	165
Total assets	10,101		10,101		9,800
Tampa Electric [Member] | Operating Segments [Member] | Revenues - External [Member]
Segment Reporting Information [Line Items]
Total revenues	531	453	977	873
Tampa Electric [Member] | Operating Segments [Member] | Intracompany Sales [Member]
Segment Reporting Information [Line Items]
Intracompany sales	1	1	2	2
PGS [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	123	97	278	227
Total interest charges	5	4	10	8
Net income	19	11	46	29
Total assets	2,021		2,021		$ 1,901
PGS [Member] | Operating Segments [Member] | Revenues - External [Member]
Segment Reporting Information [Line Items]
Total revenues	123	96	276	223
PGS [Member] | Operating Segments [Member] | Intracompany Sales [Member]
Segment Reporting Information [Line Items]
Intracompany sales	$ 0	$ 1	$ 2	$ 4

Revenue - Summary of Disaggrega

Revenue - Summary of Disaggregates TEC Revenue by Major Source (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation Of Revenue [Line Items]
Total electric revenue	$ 531	$ 453	$ 977	$ 873
Total gas revenue	123	96	276	223
Total revenue	654	549	1,253	1,096
Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	276	254	508	459
Total gas revenue	49	36	116	84
Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	144	121	270	246
Total gas revenue	46	28	99	69
Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	41	32	78	69
Total gas revenue	6	5	12	11
Regulatory Deferrals and Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	11	(3)	9	(5)
Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	59	49	112	104
Total gas revenue	22	27	49	59
Operating Segments [Member] | Tampa Electric [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	532	454	979	875
Total gas revenue	0	0	0	0
Total revenue	532	454	979	875
Operating Segments [Member] | Tampa Electric [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	276	254	508	459
Total gas revenue	0	0	0	0
Operating Segments [Member] | Tampa Electric [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	144	121	270	246
Total gas revenue	0	0	0	0
Operating Segments [Member] | Tampa Electric [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	41	32	78	69
Total gas revenue	0	0	0	0
Operating Segments [Member] | Tampa Electric [Member] | Regulatory Deferrals and Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	11	(3)	9	(5)
Operating Segments [Member] | Tampa Electric [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	60	50	114	106
Total gas revenue	0	0	0	0
Operating Segments [Member] | PGS [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Total gas revenue	123	97	278	227
Total revenue	123	97	278	227
Operating Segments [Member] | PGS [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Total gas revenue	49	36	116	84
Operating Segments [Member] | PGS [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Total gas revenue	46	28	99	69
Operating Segments [Member] | PGS [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Total gas revenue	6	5	12	11
Operating Segments [Member] | PGS [Member] | Regulatory Deferrals and Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Operating Segments [Member] | PGS [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Total gas revenue	22	28	51	63
Eliminations [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(1)	(1)	(2)	(2)
Total gas revenue	0	(1)	(2)	(4)
Total revenue	(1)	(2)	(4)	(6)
Eliminations [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Total gas revenue	0	0	0	0
Eliminations [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Total gas revenue	0	0	0	0
Eliminations [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Total gas revenue	0	0	0	0
Eliminations [Member] | Regulatory Deferrals and Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	0	0	0	0
Eliminations [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(1)	(1)	(2)	(2)
Total gas revenue	$ 0	$ (1)	$ (2)	$ (4)

Revenue - Additional Informatio

Revenue - Additional Information (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Regulated Operating Revenue [Abstract]
Remaining performance obligations, transaction price	$ 130	$ 135
Remaining performance obligations, expected year of revenue recognition	2033