Tampa Electric 10-Q 2 May 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2014	Apr. 25, 2014
Document Information [Line Items]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Trading Symbol	'TE	'
Entity Registrant Name	'TECO ENERGY INC	'
Entity Central Index Key	'0000350563	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	217,805,680
Tampa Electric Company [Member]	'	'
Document Information [Line Items]	'	'
Entity Registrant Name	'TAMPA ELECTRIC COMPANY	'
Entity Central Index Key	'0000096271	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Non-accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	10

Consolidated_Condensed_Balance

Consolidated Condensed Balance Sheets (Unaudited) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Current assets	'	'
Cash and cash equivalents	$137	$185.20
Receivables, less allowance for uncollectibles	269.1	287.2
Inventories, at average cost	'	'
Derivative assets	15.6	9.7
Regulatory assets	32.7	34.3
Deferred income taxes	89	100.3
Prepayments and other current assets	35.1	34.9
Income tax receivables	0.8	1.5
Total current assets	783.5	857.7
Property, plant and equipment	'	'
Construction work in progress	442.9	386.7
Other property	447.5	448.3
Property, plant and equipment, at original costs	9,185.30	9,077.30
Accumulated depreciation	-2,951.50	-2,907.20
Total property, plant and equipment, net	6,233.80	6,170.10
Other assets	'	'
Regulatory assets	288.8	293.1
Derivative assets	0.2	0.3
Deferred charges and other assets	124.4	126.8
Total other assets	413.4	420.2
Total assets	7,430.70	7,448
Current liabilities	'	'
Long-term debt due within one year	83.3	83.3
Notes payable	29	84
Accounts payable	250	261.7
Customer deposits	166.8	164.5
Regulatory liabilities	90.1	85.8
Derivative liabilities	0.1	0.1
Interest accrued	54.8	31.9
Taxes accrued	49.4	34.6
Other	18.3	19.5
Total current liabilities	741.8	765.4
Other liabilities	'	'
Deferred income taxes	461.6	444
Investment tax credits	9.3	9.4
Regulatory liabilities	625	631.4
Derivative liabilities	0.1	0.2
Deferred credits and other liabilities	421.5	426.1
Long-term debt, less amount due within one year	2,837.80	2,837.80
Total other liabilities	4,355.30	4,348.90
Commitments and contingencies (see Note 10)	'	'
Capital	'	'
Common equity	218.2	217.3
Additional paid in capital	1,585.70	1,581.30
Retained earnings	550.4	548.3
Accumulated other comprehensive loss	-20.7	-13.2
Total capital	2,333.60	2,333.70
Total liabilities and capital	7,430.70	7,448
Fuel [Member]	'	'
Inventories, at average cost	'	'
Utility inventories	120	118.7
Materials and supplies [Member]	'	'
Inventories, at average cost	'	'
Utility inventories	84.2	85.9
Electric [Member]	'	'
Property, plant and equipment	'	'
Public utilities, property, plant and equipment	6,982.40	6,934
Gas [Member]	'	'
Property, plant and equipment	'	'
Public utilities, property, plant and equipment	1,312.50	1,308.30
Tampa Electric Company [Member]	'	'
Current assets	'	'
Cash and cash equivalents	16.9	9.8
Receivables, less allowance for uncollectibles	214.9	227.6
Inventories, at average cost	'	'
Derivative assets	32.7	34.3
Regulatory assets	15.5	9.5
Deferred income taxes	20.1	29.4
Prepayments and other current assets	12.7	12.5
Income tax receivables	0	54.9
Total current assets	474	548.5
Property, plant and equipment	'	'
Construction work in progress	441.2	385.3
Property, plant and equipment, at original costs	8,677.20	8,568.80
Accumulated depreciation	-2,602.70	-2,562.60
Public utilities, property, plant and equipment, net	6,074.50	6,006.20
Other property	8.3	8.3
Total property, plant and equipment, net	6,082.80	6,014.50
Other assets	'	'
Unamortized debt expense	14.5	14.8
Regulatory assets	288.8	293.1
Derivative assets	0.2	0.3
Deferred charges and other assets	308.5	312.8
Other	5	4.6
Total other assets	5	4.6
Total assets	6,865.30	6,875.80
Current liabilities	'	'
Long-term debt due within one year	83.3	83.3
Notes payable	29	84
Accounts payable	216.2	226
Customer deposits	166.8	164.5
Regulatory liabilities	90.1	85.8
Interest accrued	37.3	16.4
Taxes accrued	39.7	12.2
Other	12	12
Total current liabilities	674.4	684.2
Other liabilities	'	'
Deferred income taxes	1,132.10	1,114.30
Investment tax credits	9.3	9.4
Regulatory liabilities	625	631.4
Derivative liabilities	0.1	0.2
Other	295.4	308.1
Long-term debt, less amount due within one year	1,797.50	1,797.50
Total other liabilities	2,061.90	2,063.40
Commitments and contingencies (see Note 10)	'	'
Capital	'	'
Common equity	2,037.40	2,030.40
Retained earnings	301.7	308.1
Accumulated other comprehensive loss	-7.6	-7.8
Total capital	2,331.50	2,330.70
Total capitalization	4,129	4,128.20
Total liabilities and capital	6,865.30	6,875.80
Tampa Electric Company [Member] | Fuel [Member]	'	'
Inventories, at average cost	'	'
Utility inventories	86.1	93.7
Tampa Electric Company [Member] | Materials and supplies [Member]	'	'
Inventories, at average cost	'	'
Utility inventories	75.1	76.8
Tampa Electric Company [Member] | Electric [Member]	'	'
Property, plant and equipment	'	'
Public utilities, property, plant and equipment	6,982.40	6,934
Tampa Electric Company [Member] | Gas [Member]	'	'
Property, plant and equipment	'	'
Public utilities, property, plant and equipment	$1,253.60	$1,249.50

Consolidated_Condensed_Balance1

Consolidated Condensed Balance Sheets (Unaudited) (Parenthetical) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, except Per Share data, unless otherwise specified
Allowance for uncollectibles	$4.90	$4.70
Common equity, shares authorized	400	400
Common equity, par value	$1	$1
Common equity, shares outstanding	218.2	217.3
Tampa Electric Company [Member]	'	'
Allowance for uncollectibles	$2.20	$2

Consolidated_Condensed_Stateme

Consolidated Condensed Statements of Income (Unaudited) (USD $)	3 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Revenues	'	'
Regulated electric and gas (includes franchise fees and gross receipts taxes of $27.2 in 2014 and $25.4 in 2013)	$575.70	$539.10
Unregulated	108.4	122
Total revenues	684.1	661.1
Expenses	'	'
Fuel	149.6	140
Purchased power	18.2	14.6
Cost of natural gas sold	47.1	49.5
Other	120.6	120.8
Operation and maintenance other expense	'	'
Mining related costs	91.2	95.5
Other	3.1	1.3
Depreciation and amortization	84.9	82
Taxes, other than income	56.3	53.3
Total expenses	571	557
Income from continuing operations	113.1	104.1
Other income	'	'
Allowance for other funds used during construction	2.4	1.1
Other income	-0.7	1.6
Total other income	1.7	2.7
Interest charges	'	'
Interest expense	42.5	43
Allowance for borrowed funds used during construction	-1.4	-0.6
Total interest charges	41.1	42.4
Income from continuing operations before provision for income taxes	73.7	64.4
Provision for income taxes	26.7	23.2
Net income from continuing operations	47	41.2
Discontinued operations	'	'
Income from discontinued operations	5	0.4
Provision for income taxes	1.9	0.1
Income from discontinued operations, net	3.1	0.3
Net income	$50.10	$41.50
Average common shares outstanding - Basic	215.2	214.6
Average common shares outstanding - Diluted	215.7	215.6
Earnings per share from continuing operations - Basic	$0.22	$0.19
Earnings per share from continuing operations - Diluted	$0.22	$0.19
Earnings per share from discontinued operations - Basic	$0.01	$0
Earnings per share from discontinued operations - Diluted	$0.01	$0
Earnings per share attributable to TECO Energy - Basic	$0.23	$0.19
Earnings per share attributable to TECO Energy - Diluted	$0.23	$0.19
Dividends paid per common share outstanding	$0.22	$0.22

Consolidated_Condensed_Stateme1

Consolidated Condensed Statements of Income (Unaudited) (Parenthetical) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Income Statement [Abstract]	'	'
Franchise fees and gross receipts taxes	$27.20	$25.40

Consolidated_Condensed_Stateme2

Consolidated Condensed Statements of Comprehensive Income (Unaudited) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]	'	'
Net income	$50.10	$41.50
Other comprehensive income, net of tax	'	'
Net unrealized gains on cash flow hedges	0.2	0.4
Amortization of unrecognized benefit costs	0.5	0.7
Increase in unrecognized post employment costs	-8.2	0
Other comprehensive income, net of tax	-7.5	1.1
Comprehensive income	$42.60	$42.60

Consolidated_Condensed_Stateme3

Consolidated Condensed Statements of Cash Flows (Unaudited) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities	'	'
Net income	$50.10	$41.50
Adjustments to reconcile net income to net cash from operating activities:	'	'
Depreciation and amortization	84.9	82
Depreciation and amortization	84.9	82
Deferred income taxes	28.9	23.4
Investment tax credits	-0.1	-0.1
Allowance for funds used during construction	-2.4	-1.1
Non-cash stock compensation	3.7	3.6
Gain on sales of business/assets, pretax	-0.1	-0.2
Deferred recovery clauses	2.6	4.5
Receivables, less allowance for uncollectibles	18.1	13
Inventories	0.4	-21.4
Prepayments and other current assets	-0.2	0.6
Taxes accrued	15.5	15.8
Interest accrued	22.9	22.1
Accounts payable	-25.2	-25
Other	-12.2	-0.8
Cash flows from operating activities	186.9	157.9
Cash flows from investing activities	'	'
Capital expenditures	-136.3	-103
Allowance for funds used during construction	2.4	1.1
Net proceeds from sales of business/assets	0.2	0.3
Cash flows used in investing activities	-133.7	-101.6
Cash flows from financing activities	'	'
Dividends	-48	-47.8
Common stock	1.6	3.9
Net decrease in short-term debt	-55	0
Cash flows used in financing activities	-101.4	-43.9
Net (decrease) increase in cash and cash equivalents	-48.2	12.4
Cash and cash equivalents at beginning of period	185.2	200.5
Cash and cash equivalents at end of period	137	212.9
Supplemental disclosure of non-cash activities	'	'
Capital expenditures not yet paid	14.6	0.6
Tampa Electric Company [Member]	'	'
Cash flows from operating activities	'	'
Net income	59.8	45.6
Adjustments to reconcile net income to net cash from operating activities:	'	'
Depreciation and amortization	75.4	72
Deferred income taxes	22.8	23.3
Investment tax credits	-0.1	-0.1
Allowance for funds used during construction	-2.4	-1.1
Deferred recovery clauses	2.6	4.5
Receivables, less allowance for uncollectibles	12.7	2.2
Inventories	9.3	-17.2
Prepayments	-0.2	-0.1
Taxes accrued	82.4	39.1
Interest accrued	20.9	20.2
Accounts payable	-23.3	-21.1
Other	-9.1	-0.7
Cash flows from operating activities	250.8	166.6
Cash flows from investing activities	'	'
Capital expenditures	-132	-97.9
Allowance for funds used during construction	2.4	1.1
Cash flows used in investing activities	-129.6	-96.8
Cash flows from financing activities	'	'
Dividends	-66.1	-55
Common stock	7	0
Net decrease in short-term debt	-55	0
Cash flows used in financing activities	-114.1	-55
Net (decrease) increase in cash and cash equivalents	7.1	14.8
Cash and cash equivalents at beginning of period	9.8	45.2
Cash and cash equivalents at end of period	16.9	60
Supplemental disclosure of non-cash activities	'	'
Capital expenditures not yet paid	$14.70	$0.60

Consolidated_Condensed_Stateme4

Consolidated Condensed Statements of Income and Comprehensive Income (Unaudited) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Revenues	'	'
Total revenues	$684.10	$661.10
Expenses	'	'
Fuel	149.6	140
Purchased power	18.2	14.6
Cost of natural gas sold	47.1	49.5
Other	120.6	120.8
Depreciation and amortization	84.9	82
Taxes, other than income	56.3	53.3
Total expenses	571	557
Income from operations	113.1	104.1
Other income	'	'
Allowance for other funds used during construction	2.4	1.1
Total other income	1.7	2.7
Interest charges	'	'
Interest on long-term debt	42.5	43
Allowance for borrowed funds used during construction	-1.4	-0.6
Total interest charges	41.1	42.4
Income before provision for income taxes	73.7	64.4
Provision for income taxes	26.7	23.2
Net income	50.1	41.5
Other comprehensive income, net of tax	'	'
Total other comprehensive income, net of tax	-7.5	1.1
Comprehensive income	42.6	42.6
Tampa Electric Company [Member]	'	'
Revenues	'	'
Electric (includes franchise fees and gross receipts taxes of $20.3 in 2014 and $19.0 in 2013)	453	417.9
Gas (includes franchise fees and gross receipts taxes of $6.9 in 2014 and $6.4 in 2013)	122.5	121.9
Total revenues	575.5	539.8
Expenses	'	'
Fuel	149.6	140
Purchased power	18.2	14.6
Cost of natural gas sold	47.2	49.5
Other	120.3	120.6
Depreciation and amortization	75.4	72
Taxes, other than income	47.4	44.5
Total expenses	458.1	441.2
Income from operations	117.4	98.6
Other income	'	'
Allowance for other funds used during construction	2.4	1.1
Other income, net	1.2	1.2
Total other income	3.6	2.3
Interest charges	'	'
Interest on long-term debt	25.7	26.5
Other interest	1.1	0.9
Allowance for borrowed funds used during construction	-1.4	-0.6
Total interest charges	25.4	26.8
Income before provision for income taxes	95.6	74.1
Provision for income taxes	35.8	28.5
Net income	59.8	45.6
Other comprehensive income, net of tax	'	'
Amortization of settled interest rate swaps	0.2	0.2
Total other comprehensive income, net of tax	0.2	0.2
Comprehensive income	$60	$45.80

Consolidated_Condensed_Stateme5

Consolidated Condensed Statements of Income and Comprehensive Income (Unaudited) (Parenthetical) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Franchise fees and gross receipts taxes	$27.20	$25.40
Tampa Electric Company [Member]	'	'
Franchise fees and gross receipts taxes	27.2	25.4
Tampa Electric Company [Member] | Electric [Member]	'	'
Franchise fees and gross receipts taxes	20.3	19
Tampa Electric Company [Member] | Gas [Member]	'	'
Franchise fees and gross receipts taxes	$6.90	$6.40

Summary_of_Significant_Account

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2014
Summary of Significant Accounting Policies	'
	1. Summary of Significant Accounting Policies
	See TECO Energy, Inc.’s 2013 Annual Report on Form 10-K for a complete detailed discussion of accounting policies. The significant accounting policies for both utility and diversified operations include:
	Principles of Consolidation and Basis of Presentation
	The consolidated condensed financial statements include the accounts of TECO Energy, Inc., its majority-owned and controlled subsidiaries and the accounts of VIEs for which it is the primary beneficiary (TECO Energy or the company). TECO Energy is considered to be the primary beneficiary of VIEs if it has both 1) the power to direct the activities of a VIE that most significantly impact the entity’s economic performance and 2) the obligation to absorb losses of the entity that could potentially be significant to the VIE or the right to receive benefits from the entity that could potentially be significant to the VIE. For the periods presented, no VIEs have been consolidated in continuing operations (see Note 14).
	All significant intercompany balances and intercompany transactions 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 TECO Energy, Inc. and its subsidiaries as of March 31, 2014 and Dec. 31, 2013, and the results of operations and cash flows for the periods ended March 31, 2014 and 2013. The results of operations for the three months ended March 31, 2014 are not necessarily indicative of the results that can be expected for the entire fiscal year ending Dec. 31, 2014.
	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 data 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.
	Revenues
	As of March 31, 2014 and Dec. 31, 2013, unbilled revenues of $48.1 million and $46.7 million, respectively, are included in the “Receivables” line item on the Consolidated Condensed Balance Sheets.
	Accounting for Excise Taxes, Franchise Fees and Gross Receipts
	TECO Coal incurs most of TECO Energy’s total excise taxes, which are accrued as an expense and reconciled to the actual cash payment of excise taxes. As general expenses, they are not specifically recovered through revenues. Excise taxes paid by the regulated utilities are not material and are expensed when incurred.
	The regulated utilities are allowed to recover certain costs on a dollar-per-dollar basis incurred from customers through prices 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 the regulated utilities are included as an expense on the Consolidated Condensed Statements of Income in “Taxes, other than income”. These amounts totaled $27.2 million and $25.4 million for the three months ended March 31, 2014 and 2013, respectively.
	Cash Flows Related to Derivatives and Hedging Activities
	The company classifies cash inflows and outflows related to derivative and hedging instruments in the appropriate cash flow sections associated with the item being hedged. In the case of diesel fuel swaps, which are used to mitigate the fluctuations in the price of diesel fuel, the cash inflows and outflows are included in the operating section. For natural gas and ongoing interest rate swaps, the cash inflows and outflows are included in the operating section. For interest rate swaps that settle coincident with the debt issuance, the cash inflows and outflows are treated as premiums or discounts and included in the financing section of the Consolidated Condensed Statements of Cash Flows.
	Reclassifications
	Certain reclassifications were made to prior year amounts to conform to current period presentation. None of the reclassifications affected TECO Energy’s net income in any period.
Tampa Electric Company [Member]	'
Summary of Significant Accounting Policies	'
	1. Summary of Significant Accounting Policies
	See TEC’s 2013 Annual Report on Form 10-K for a complete detailed 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, Inc. For the purposes of its consolidated financial reporting, TEC is comprised of the electric division, generally referred to as Tampa Electric, the natural gas division, generally referred to as PGS, and potentially the accounts of VIEs for which it is the primary beneficiary. For the periods presented, no VIEs have been consolidated (see Note 13).
	All significant intercompany balances and intercompany transactions 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 March 31, 2014 and Dec. 31, 2013, and the results of operations and cash flows for the periods ended March 31, 2014 and 2013. The results of operations for the three months ended March 31, 2014 are not necessarily indicative of the results that can be expected for the entire fiscal year ending Dec. 31, 2014.
	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 data 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.
	Revenues
	As of March 31, 2014 and Dec. 31, 2013, unbilled revenues of $48.1 million and $46.7 million, respectively, are included in the “Receivables” line item on the Consolidated Condensed Balance Sheets.
	Accounting for Franchise Fees and Gross Receipts
	The regulated utilities are allowed to recover certain costs on a dollar-per-dollar basis incurred from customers through prices 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 the regulated utilities are included as an expense on the Consolidated Condensed Statements of Income in “Taxes, other than income”. These amounts totaled $27.2 million and $25.4 million for the three months ended March 31, 2014 and 2013, respectively.
	Cash Flows Related to Derivatives and Hedging Activities
	TEC classifies cash inflows and outflows related to derivative and hedging instruments in the appropriate cash flow sections associated with the item being hedged. For natural gas and ongoing interest rate swaps, the cash inflows and outflows are included in the operating section. For interest rate swaps that settle coincident with the debt issuance, the cash inflows and outflows are treated as premiums or discounts and included in the financing section of the Consolidated Condensed Statements of Cash Flows.
	Reclassifications
	Certain reclassifications were made to prior year amounts to conform to current period presentation. Income tax expense related to regulated operations was previously included within income from operations as it is part of the determination of utility revenue requirements. Income tax expense is now presented directly above net income to conform to the TECO Energy, Inc. presentation. For prior periods, this change results in an increase in income from operations for the amount of income tax expense reclassified. None of the reclassifications affected TEC’s net income in any period.

New_Accounting_Pronouncements

New Accounting Pronouncements	3 Months Ended
	Mar. 31, 2014
New Accounting Pronouncements	'
	2. New Accounting Pronouncements
	Unrecognized Tax Benefits
	In July 2013, the FASB issued guidance regarding the presentation of unrecognized tax benefits in the statement of position when a net operating loss carryforward, a similar tax loss or a tax credit carryforward exists. It requires that an unrecognized tax benefit be presented as a reduction to a deferred tax asset for net operating loss carryforwards, similar tax losses or tax credit carryforwards, with certain exceptions. The guidance became effective for interim and annual reporting periods beginning on or after Dec. 15, 2013. The company has adopted this guidance and it has no effect on the company’s results of operations, financial position or cash flows.
Tampa Electric Company [Member]	'
New Accounting Pronouncements	'
	2. New Accounting Pronouncements
	Unrecognized Tax Benefits
	In July 2013, the FASB issued guidance regarding the presentation of unrecognized tax benefits in the statement of position when a net operating loss carryforward, a similar tax loss or a tax credit carryforward exists. It requires that an unrecognized tax benefit be presented as a reduction to a deferred tax asset for net operating loss carryforwards, similar tax losses or tax credit carryforwards, with certain exceptions. The guidance became effective for interim and annual reporting periods beginning on or after Dec. 15, 2013. TEC has adopted this guidance and it has no effect on TEC’s results of operations, financial position or cash flows.

Regulatory

Regulatory	3 Months Ended
	Mar. 31, 2014
Regulatory	'
	3. Regulatory
	Tampa Electric’s and PGS’s retail businesses are regulated by the FPSC. Tampa Electric is also subject to regulation by the FERC under PUHCA 2005. However, pursuant to a waiver granted in accordance with the FERC’s regulations, TECO Energy is not subject to certain accounting, record-keeping and reporting requirements prescribed by the FERC’s regulations under PUHCA 2005. The operations of PGS are regulated by the FPSC separately from the operations of Tampa Electric. The FPSC has jurisdiction over rates, service, issuance of securities, safety, accounting and depreciation practices and other matters. In general, the FPSC sets rates at a level that allows utilities such as Tampa Electric and PGS to collect total revenues (revenue requirements) equal to their cost of providing service, plus a reasonable return on invested capital.
	Storm Damage Cost Recovery
	Prior to Nov. 1, 2013, Tampa Electric was accruing $8.0 million annually to a FERC-authorized and FPSC-approved self-insured storm damage reserve. This reserve was created after Florida’s IOUs were unable to obtain transmission and distribution insurance coverage due to destructive acts of nature. Effective Nov. 1, 2013, Tampa Electric ceased accruing for this storm damage reserve as a result of the 2013 rate case settlement. However, 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 $56.1 million; the level it was as of Oct. 31, 2013. Tampa Electric’s storm reserve remained $56.1 million at both March 31, 2014 and Dec. 31, 2013.
	Regulatory Assets and Liabilities
	Tampa Electric and PGS maintain their accounts in accordance with recognized policies of the FPSC. In addition, Tampa Electric maintains its accounts in accordance with recognized policies prescribed or permitted by the FERC.
	Tampa Electric and PGS apply the accounting standards for regulated operations. Areas of applicability include: deferral of revenues under approved regulatory agreements; revenue recognition resulting from cost-recovery clauses that provide for monthly billing charges to reflect increases or decreases in fuel, purchased power, conservation and environmental costs; and the deferral of costs as regulatory assets to the period in which the regulatory agency recognizes them, when cost recovery is ordered over a period longer than a fiscal year.
	Details of the regulatory assets and liabilities as of March 31, 2014 and Dec. 31, 2013 are presented in the following table:
	Regulatory Assets and Liabilities
	(millions)		Mar. 31,		Dec. 31,
			2014		2013
	Regulatory assets:
	Regulatory tax asset (1)		$	67.9	$	67.4
	Other:
	Cost-recovery clauses			3.3		6.1
	Postretirement benefit asset			180.2		182.7
	Deferred bond refinancing costs (2)			7.8		8
	Environmental remediation			51.4		51.4
	Competitive rate adjustment			3.4		4.1
	Other			7.5		7.7
	Total other regulatory assets			253.6		260
	Total regulatory assets			321.5		327.4
	Less: Current portion			32.7		34.3
	Long-term regulatory assets		$	288.8	$	293.1
	Regulatory liabilities:
	Regulatory tax liability (1)		$	5.8	$	9.8
	Other:
	Cost-recovery clauses			58.9		54.5
	Transmission and delivery storm reserve			56.1		56.1
	Deferred gain on property sales (3)			1.7		2
	Provision for stipulation and other			0.8		0.8
	Accumulated reserve - cost of removal			591.8		594
	Total other regulatory liabilities			709.3		707.4
	Total regulatory liabilities			715.1		717.2
	Less: Current portion			90.1		85.8
	Long-term regulatory liabilities		$	625	$	631.4
	-1	Primarily related to plant life and derivative positions.
	-2	Amortized over the term of the related debt instruments.
	-3	Amortized over a 5-year period with various ending dates.
	All regulatory assets are recovered through the regulatory process. The following table further details the regulatory assets and the related recovery periods:
	Regulatory Assets
	(millions)		Mar. 31,		Dec. 31,
			2014		2013
	Clause recoverable (1)		$	6.7	$	10.2
	Components of rate base (2)			183.2		185.6
	Regulatory tax assets (3)			67.9		67.4
	Capital structure and other (3)			63.7		64.2
	Total		$	321.5	$	327.4
	-1	To be recovered through cost-recovery clauses approved by the FPSC on a dollar-for-dollar basis in the next year.
	-2	Primarily reflects allowed working capital, which is included in rate base and earns a rate of return as permitted by the FPSC.
	-3	“Regulatory tax assets” and “Capital structure and other” regulatory assets have a recoverable period longer than a fiscal year and are recognized over the period authorized by the regulatory agency. Also included are unamortized loan costs, which are amortized over the life of the related debt instruments. See footnotes 1 and 2 in the prior table for additional information.
Tampa Electric Company [Member]	'
Regulatory	'
	3. Regulatory
	Tampa Electric’s and PGS’s retail businesses are regulated by the FPSC. Tampa Electric is also subject to regulation by the FERC under PUHCA 2005. However, pursuant to a waiver granted in accordance with the FERC’s regulations, TECO Energy is not subject to certain accounting, record-keeping and reporting requirements prescribed by the FERC’s regulations under PUHCA 2005. The operations of PGS are regulated by the FPSC separately from the operations of Tampa Electric. The FPSC has jurisdiction over rates, service, issuance of securities, safety, accounting and depreciation practices and other matters. In general, the FPSC sets rates at a level that allows utilities such as Tampa Electric and PGS to collect total revenues (revenue requirements) equal to their cost of providing service, plus a reasonable return on invested capital.
	Storm Damage Cost Recovery
	Prior to Nov. 1, 2013, Tampa Electric was accruing $8.0 million annually to a FERC-authorized and FPSC-approved self-insured storm damage reserve. This reserve was created after Florida’s IOUs were unable to obtain transmission and distribution insurance coverage due to destructive acts of nature. Effective Nov. 1, 2013, Tampa Electric ceased accruing for this storm damage reserve as a result of the 2013 rate case settlement. However, 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 $56.1 million; the level it was as of Oct. 31, 2013. Tampa Electric’s storm reserve remained $56.1 million at both March 31, 2014 and Dec. 31, 2013.
	Regulatory Assets and Liabilities
	Tampa Electric and PGS maintain their accounts in accordance with recognized policies of the FPSC. In addition, Tampa Electric maintains its accounts in accordance with recognized policies prescribed or permitted by the FERC.
	Tampa Electric and PGS apply the accounting standards for regulated operations. Areas of applicability include: deferral of revenues under approved regulatory agreements; revenue recognition resulting from cost-recovery clauses that provide for monthly billing charges to reflect increases or decreases in fuel, purchased power, conservation and environmental costs; and the deferral of costs as regulatory assets to the period in which the regulatory agency recognizes them, when cost recovery is ordered over a period longer than a fiscal year.
	Details of the regulatory assets and liabilities as of March 31, 2014 and Dec. 31, 2013 are presented in the following table:
	Regulatory Assets and Liabilities
			Mar. 31,		Dec. 31,
	(millions)		2014		2013
	Regulatory assets:
	Regulatory tax asset (1)		$	67.9	$	67.4
	Other:
	Cost-recovery clauses			3.3		6.1
	Postretirement benefit asset			180.2		182.7
	Deferred bond refinancing costs (2)			7.8		8
	Environmental remediation			51.4		51.4
	Competitive rate adjustment			3.4		4.1
	Other			7.5		7.7
	Total other regulatory assets			253.6		260
	Total regulatory assets			321.5		327.4
	Less: Current portion			32.7		34.3
	Long-term regulatory assets		$	288.8	$	293.1
	Regulatory liabilities:
	Regulatory tax liability (1)		$	5.8	$	9.8
	Other:
	Cost-recovery clauses			58.9		54.5
	Transmission and delivery storm reserve			56.1		56.1
	Deferred gain on property sales (3)			1.7		2
	Provision for stipulation and other			0.8		0.8
	Accumulated reserve - cost of removal			591.8		594
	Total other regulatory liabilities			709.3		707.4
	Total regulatory liabilities			715.1		717.2
	Less: Current portion			90.1		85.8
	Long-term regulatory liabilities		$	625	$	631.4
	-1	Primarily related to plant life and derivative positions.
	-2	Amortized over the term of the related debt instruments.
	-3	Amortized over a 5-year period with various ending dates.
	All regulatory assets are recovered through the regulatory process. The following table further details the regulatory assets and the related recovery periods:
	Regulatory Assets
			Mar. 31,		Dec. 31,
	(millions)		2014		2013
	Clause recoverable (1)		$	6.7	$	10.2
	Components of rate base (2)			183.2		185.6
	Regulatory tax assets (3)			67.9		67.4
	Capital structure and other (3)			63.7		64.2
	Total		$	321.5	$	327.4
	-1	To be recovered through cost-recovery clauses approved by the FPSC on a dollar-for-dollar basis in the next year.
	-2	Primarily reflects allowed working capital, which is included in rate base and earns a rate of return as permitted by the FPSC.
	-3	“Regulatory tax assets” and “Capital structure and other” regulatory assets have a recoverable period longer than a fiscal year and are recognized over the period authorized by the regulatory agency. Also included are unamortized loan costs, which are amortized over the life of the related debt instruments. See footnotes 1 and 2 in the prior table for additional information.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2014
Income Taxes	'
	4. Income Taxes
	The company’s U.S. subsidiaries join in the filing of a U.S. federal consolidated income tax return. The IRS concluded its examination of the company’s 2012 consolidated federal income tax return in January 2014. The U.S. federal statute of limitations remains open for years 2010 and forward. Years 2013 and 2014 are currently under examination by the IRS under its Compliance Assurance Program. TECO Energy does not expect the results of current IRS examinations to significantly change the total amount of unrecognized tax benefits by the end of 2014. U.S. state jurisdictions have statutes of limitations generally ranging from three to four years from the filing of an income tax return. The state impact of any federal changes remains subject to examination by various states for a period of up to one year after formal notification to the states. Years still open to examination by tax authorities in major state and foreign jurisdictions include 2010 and forward.
	The effective tax rate increased to 36.22% for the three months ended March 31, 2014 from 35.95% for the same period in 2013.
Tampa Electric Company [Member]	'
Income Taxes	'
	4. Income Taxes
	TEC is included in the filing of a consolidated federal income tax return with TECO Energy and its affiliates. TEC’s income tax expense is based upon a separate return computation. TEC’s effective tax rates for the three months ended March 31, 2014 and 2013 differ from the statutory rate principally due to state income taxes, the domestic activity production deduction and the AFUDC-equity.
	The IRS concluded its examination of TECO Energy’s 2012 consolidated federal income tax return in January 2014. The U.S. federal statute of limitations remains open for the year 2010 and forward. Years 2013 and 2014 are currently under examination by the IRS under its Compliance Assurance Program. TECO Energy does not expect the results of current IRS examinations to significantly change the total amount of unrecognized tax benefits by the end of 2014. Florida’s statute of limitations is three years from the filing of an income tax return. The state impact of any federal changes remains subject to examination by various states for a period of up to one year after formal notification to the states. Years still open to examination by Florida’s tax authorities include 2010 and forward.

Employee_Postretirement_Benefi

Employee Postretirement Benefits	3 Months Ended
	Mar. 31, 2014
Employee Postretirement Benefits	'
	5. Employee Postretirement Benefits
	Included in the table below is the periodic expense for pension and other postretirement benefits offered by the company.
	Pension Expense
	(millions)	Pension Benefits						Other Postretirement Benefits
	Three months ended Mar. 31,	2014			2013			2014		2013
	Components of net periodic benefit expense
	Service cost	$	4.1		$	4.8		$	0.6	$	0.7
	Interest cost on projected benefit obligations		8.2			7.2			2.6		2.3
	Expected return on assets		(10.3	)		(9.7	)		0		0
	Amortization of:
	Prior service cost		(0.1	)		(0.1	)		0		(0.1	)
	Actuarial loss		3.2			5			0		0.3
	Net pension expense recognized in the Consolidated Condensed Statements of Income	$	5.1		$	7.2		$	3.2	$	3.2
	For the fiscal 2014 plan year, TECO Energy is using an assumed long-term EROA of 7.25% and a discount rate of 5.118% for pension benefits under its qualified pension plan, and a discount rate of 5.096% for its other postretirement benefits as of their Jan. 1, 2014 measurement dates. Additionally, TECO Energy made contributions of $16.0 million to its pension plan in the first quarter of 2014.
	For the three months ended March 31, 2014, TECO Energy and its subsidiaries reclassed $0.6 million pretax of unamortized prior service benefit and actuarial losses from AOCI to net income as part of periodic benefit expense. In addition, during the three months ended March 31, 2014, TEC reclassed $2.5 million of unamortized prior service benefit and actuarial losses from regulatory assets to net income as part of periodic benefit expense.
Tampa Electric Company [Member]	'
Employee Postretirement Benefits	'
	5. Employee Postretirement Benefits
	TEC is a participant in the comprehensive retirement plans of TECO Energy. Amounts allocable to all participants of the TECO Energy retirement plans are found in Note 5, Employee Postretirement Benefits, in the TECO Energy, Inc. Notes to Consolidated Condensed Financial Statements. TEC’s portion of the net pension expense for the three months ended March 31, 2014 and 2013, respectively, was $3.8 million and $5.3 million for pension benefits, and $2.6 million and $2.6 million for other postretirement benefits.
	For the fiscal 2014 plan year, TECO Energy assumed a long-term EROA of 7.25% and a discount rate of 5.118% for pension benefits under its qualified pension plan, and a discount rate of 5.096% for its other postretirement benefits as of their Jan. 1, 2014 measurement dates. Additionally, TECO Energy made contributions of $16.0 million to its pension plan in the first quarter of 2014. TEC’s portion of the contributions was $13.0 million.
	Included in the benefit expenses discussed above, for the three months ended March 31, 2014, TEC reclassed $2.5 million of unamortized prior service benefit and actuarial losses from regulatory assets to net income.

ShortTerm_Debt

Short-Term Debt	3 Months Ended
	Mar. 31, 2014
Short-Term Debt	'
	6. Short-Term Debt
	At March 31, 2014 and Dec. 31, 2013, the following credit facilities and related borrowings existed:
	Credit Facilities
			Mar. 31, 2014						Dec. 31, 2013
	(millions)		Credit		Borrowings		Letters of		Credit		Borrowings		Letters of
			Facilities		Outstanding (1)		Credit		Facilities		Outstanding (1)		Credit
							Outstanding						Outstanding
	Tampa Electric Company:
	5-year facility (2)		$	325	$	0	$	0.7	$	325	$	6	$	0.7
	1-year accounts receivable facility			150		29		0		150		78		0
	TECO Energy/TECO Finance:
	5-year facility (2)(3)			200		0		0		200		0		0
	Total		$	675	$	29	$	0.7	$	675	$	84	$	0.7
	-1	Borrowings outstanding are reported as notes payable.
	-2	This 5-year facility matures Dec. 17, 2018.
	-3	TECO Finance is the borrower and TECO Energy is the guarantor of this facility.
	At March 31, 2014, these credit facilities require commitment fees ranging from 12.5 to 30.0 basis points. The weighted-average interest rate on outstanding amounts payable under the credit facilities at March 31, 2014 and Dec. 31, 2013 was 0.63% and 0.56%, respectively.
	Tampa Electric Company Accounts Receivable Facility
	On Feb. 14, 2014, TEC and TRC amended their $150 million accounts receivable collateralized borrowing facility, entering into Amendment No. 12 to the Loan and Servicing Agreement with certain lenders named therein and Citibank, N.A. as Program Agent. The amendment (i) extends the maturity date to Feb. 13, 2015, (ii) provides that TRC will pay program and liquidity fees, which will total 70.0 basis points, (iii) continues to provide that the interest rates on the borrowings will be based on prevailing asset-backed commercial paper rates, unless such rates are not available from conduit lenders, in which case the rates will be at an interest rate equal to, at TEC’s option, either Citibank’s prime rate (or the federal funds rate plus 50 basis points, if higher) or a rate based on the LIBOR (if available) plus a margin, (iv) confirms that CAFCO, LLC will be the Committed Lender and Conduit Lender and (v) makes other technical changes.
Tampa Electric Company [Member]	'
Short-Term Debt	'
	6. Short-Term Debt
	At March 31, 2014 and Dec. 31, 2013, the following credit facilities and related borrowings existed:
	Credit Facilities
			Mar. 31, 2014						Dec. 31, 2013
	(millions)		Credit		Borrowings		Letters of		Credit		Borrowings		Letters of
			Facilities		Outstanding (1)		Credit		Facilities		Outstanding (1)		Credit
							Outstanding						Outstanding
	Tampa Electric Company:
	5-year facility (2)		$	325	$	0	$	0.7	$	325	$	6	$	0.7
	1-year accounts receivable facility			150		29		0		150		78		0
	Total		$	475	$	29	$	0.7	$	475	$	84	$	0.7
	-1	Borrowings outstanding are reported as notes payable.
	-2	This 5-year facility matures Dec. 17, 2018.
	At March 31, 2013, these credit facilities require commitment fees ranging from 12.5 to 30.0 basis points. The weighted-average interest rate on outstanding amounts payable under the credit facilities at March 31, 2014 and Dec. 31, 2013 was 0.63% and 0.56%, respectively.
	Tampa Electric Company Accounts Receivable Facility
	On Feb. 14, 2014, TEC and TRC amended their $150 million accounts receivable collateralized borrowing facility, entering into Amendment No. 12 to the Loan and Servicing Agreement with certain lenders named therein and Citibank, N.A. as Program Agent. The amendment (i) extends the maturity date to Feb. 13, 2015, (ii) provides that TRC will pay program and liquidity fees, which will total 70.0 basis points, (iii) continues to provide that the interest rates on the borrowings will be based on prevailing asset-backed commercial paper rates, unless such rates are not available from conduit lenders, in which case the rates will be at an interest rate equal to, at TEC’s option, either Citibank’s prime rate (or the federal funds rate plus 50 basis points, if higher) or a rate based on the LIBOR (if available) plus a margin, (iv) confirms that CAFCO, LLC will be the Committed Lender and Conduit Lender and (v) makes other technical changes.

LongTerm_Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2014
Long-Term Debt	'
	7. Long-Term Debt
	Fair Value of Long-Term Debt
	At March 31, 2014, total long-term debt had a carrying amount of $2,921.1 million and an estimated fair market value of $3,209.7 million. At Dec. 31, 2013, total long-term debt had a carrying amount of $2,921.1 million and an estimated fair market value of $3,184.1 million. The company uses the market approach in determining fair value. The majority of the outstanding debt is valued using real-time financial market data obtained from Bloomberg Professional Service. The remaining securities are valued using prices obtained from the Municipal Securities Rulemaking Board and by applying estimated credit spreads obtained from a third party to the par value of the security. All debt securities are Level 2 instruments.
Tampa Electric Company [Member]	'
Long-Term Debt	'
	7. Long-Term Debt
	Fair Value of Long-Term Debt
	At March 31, 2014, TEC’s total long-term debt had a carrying amount of $1,880.8 million and an estimated fair market value of $2,058.4 million. At Dec. 31, 2013, total long-term debt had a carrying amount of $1,880.8 million and an estimated fair market value of $2,042.0 million. TEC uses the market approach in determining fair value. The majority of the outstanding debt is valued using real-time financial market data obtained from Bloomberg Professional Service. The remaining securities are valued using prices obtained from the Municipal Securities Rulemaking Board and by applying estimated credit spreads obtained from a third party to the par value of the security. All debt securities are Level 2 instruments.

Other_Comprehensive_Income

Other Comprehensive Income	3 Months Ended
	Mar. 31, 2014
Other Comprehensive Income	'
	8. Other Comprehensive Income
	TECO Energy reported the following OCI for the three months ended March 31, 2014 and 2013, related to changes in the fair value of cash flow hedges and amortization of unrecognized benefit costs associated with the company’s postretirement plans:
	Other Comprehensive Income
			Three months ended Mar. 31,
	(millions)		Gross			Tax			Net
	2014
	Unrealized loss on cash flow hedges		($	0.1	)	$	0		($	0.1	)
	Reclassification from AOCI to net income (1)			0.4			(0.1	)		0.3
	Gain on cash flow hedges			0.3			(0.1	)		0.2
	Amortization of unrecognized benefit costs (2)			0.8			(0.3	)		0.5
	Increase in unrecognized post employment costs (3)			(12.9	)		4.7			(8.2	)
	Total other comprehensive loss		($	11.8	)	$	4.3		($	7.5	)
	2013
	Unrealized gain on cash flow hedges		$	0.3		($	0.1	)	$	0.2
	Reclassification from AOCI to net income (1)			0.3			(0.1	)		0.2
	Gain on cash flow hedges			0.6			(0.2	)		0.4
	Amortization of unrecognized benefit costs (2)			1.1			(0.4	)		0.7
	Total other comprehensive income		$	1.7		($	0.6	)	$	1.1
	-1	Related to interest rate contracts recognized in Interest expense and commodity contracts recognized in Mining related costs.
	-2	Related to postretirement benefits. See Note 5 for additional information.
	-3	Amount reflects an out-of-period adjustment to unfunded black lung liability.
	Accumulated Other Comprehensive Loss
	(millions)		Mar. 31, 2014			Dec. 31, 2013
	Unrecognized pension loss and prior service credit (1)		($	20	)	($	20.5	)
	Unrecognized other benefit loss, prior service cost and transition obligation (2)			6.9			15.1
	Net unrealized losses from cash flow hedges (3)			(7.6	)		(7.8	)
	Total accumulated other comprehensive loss		($	20.7	)	($	13.2	)
	-1	Net of tax benefit of $12.3 million and $12.6 million as of Mar. 31, 2014 and Dec. 31, 2013, respectively.
	-2	Net of tax expense of $4.4 million and $9.1 million as of Mar. 31, 2014 and Dec. 31, 2013, respectively.
	-3	Net of tax benefit of $4.8 million and $4.9 million as of Mar. 31, 2014 and Dec. 31, 2013, respectively.
Tampa Electric Company [Member]	'
Other Comprehensive Income	'
	12. Other Comprehensive Income
	Other Comprehensive Income		Three months ended Mar. 31,
	(millions)		Gross			Tax			Net
	2014
	Unrealized gain on cash flow hedges		$	0		$	0		$	0
	Reclassification from AOCI to net income			0.4			(0.2	)		0.2
	Gain on cash flow hedges			0.4			(0.2	)		0.2
	Total other comprehensive income (loss)		$	0.4		($	0.2	)	$	0.2
	2013
	Unrealized gain on cash flow hedges		$	0		$	0		$	0
	Reclassification from AOCI to net income			0.4			(0.2	)		0.2
	Gain on cash flow hedges			0.4			(0.2	)		0.2
	Total other comprehensive income (loss)		$	0.4		($	0.2	)	$	0.2
	Accumulated Other Comprehensive Loss
	(millions)		Mar. 31, 2014						Dec. 31, 2013
	Net unrealized losses from cash flow hedges (1)		($	7.6	)				($	7.8	)
	Total accumulated other comprehensive loss		($	7.6	)				($	7.8	)
	-1	Net of tax benefit of $4.7 million and $4.9 million as of Mar. 31, 2014 and Dec. 31, 2013, respectively.

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	9. Earnings Per Share
		For the three months ended Mar. 31,
	(millions, except per share amounts)	2014			2013
	Basic earnings per share
	Net income from continuing operations	$	47		$	41.2
	Amount allocated to nonvested participating shareholders		(0.2	)		(0.1	)
	Income before discontinued operations available to common shareholders - Basic	$	46.8		$	41.1
	Income from discontinued operations, net	$	3.1		$	0.3
	Amount allocated to nonvested participating shareholders		0			0
	Income from discontinued operations available to common shareholders - Basic	$	3.1		$	0.3
	Net income	$	50.1		$	41.5
	Amount allocated to nonvested participating shareholders		(0.2	)		(0.1	)
	Net income available to common shareholders - Basic	$	49.9		$	41.4
	Average common shares outstanding - Basic		215.2			214.6
	Earnings per share from continuing operations available to common shareholders - Basic	$	0.22		$	0.19
	Earnings per share from discontinued operations available to common shareholders - Basic	$	0.01		$	0
	Earnings per share available to common shareholders - Basic	$	0.23		$	0.19
	Diluted earnings per share
	Net income from continuing operations	$	47		$	41.2
	Amount allocated to nonvested participating shareholders		(0.2	)		(0.1	)
	Income before discontinued operations available to common shareholders - Diluted	$	46.8		$	41.1
	Income from discontinued operations, net	$	3.1		$	0.3
	Amount allocated to nonvested participating shareholders		0			0
	Income from discontinued operations available to common shareholders - Diluted	$	3.1		$	0.3
	Net income	$	50.1		$	41.5
	Amount allocated to nonvested participating shareholders		(0.2	)		(0.1	)
	Net income available to common shareholders - Diluted	$	49.9		$	41.4
	Unadjusted average common shares outstanding - Diluted		215.2			214.6
	Assumed conversion of stock options, unvested restricted stock and contingent performance shares, net		0.5			1
	Average common shares outstanding - Diluted		215.7			215.6
	Earnings per share from continuing operations available to common shareholders - Diluted	$	0.22		$	0.19
	Earnings per share from discontinued operations available to common shareholders - Diluted	$	0.01		$	0
	Earnings per share available to common shareholders - Diluted	$	0.23		$	0.19
	Anti-dilutive shares		0			0

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies	'
	10. Commitments and Contingencies
	Legal Contingencies
	From time to time, TECO Energy 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 its 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. While the outcome of such proceedings is uncertain, management does not believe that their ultimate resolution will have a material adverse effect on the company’s results of operations, financial condition or cash flows.
	Legal Proceedings
	In November 2010, heavy equipment operated at a road construction site being conducted by Posen Construction, Inc. struck a natural gas line causing a rupture and ignition of the gas and an outage in the natural gas service to Lee and Collier counties, Florida. PGS filed suit in April 2011 against Posen Construction, Inc. in Federal Court for the Middle District of Florida to recover damages for repair and restoration relating to the incident and Posen Construction, Inc. counter-claimed against PGS alleging negligence. In the first quarter of 2014, the parties entered into a settlement agreement that resolves the claims of the parties. In addition, the suit filed in November 2011 by the Posen Construction, Inc. employee operating the heavy equipment involved in the incident in Lee County Circuit Court against PGS, Posen Construction, Inc. and a PGS contractor involved in the project, seeking damages for his injuries, also remains pending.
	In addition, three former or inactive TEC employees were maintaining a suit against TEC in Hillsborough County Circuit Court, Florida for personal injuries allegedly caused by exposure to a chemical substance at one of TEC’s power stations. The suit was originally filed in 2002, and the trial judge allowed the plaintiffs to seek punitive damages in connection with their case. In the first quarter of 2014 all plaintiffs voluntarily dismissed their suits with prejudice.
	The company believes the claims in each of the pending actions described above in this item are without merit and intends to defend each matter vigorously. The company is unable at this time to estimate the possible loss or range of loss with respect to these matters.
	Superfund and Former Manufactured Gas Plant Sites
	TEC, through its Tampa Electric and Peoples Gas divisions, is a PRP for certain superfund sites and, through its Peoples Gas division, for certain former manufactured gas plant sites. While the joint and several liability associated with these sites presents the potential for significant response costs, as of March 31, 2014 TEC has estimated its ultimate financial liability to be $38.4 million, primarily at PGS. This amount has been accrued and is primarily reflected in the long-term liability section under “Other” on the Consolidated Condensed Balance Sheets. The environmental remediation costs associated with these sites, which are expected to be paid over many years, are not expected to have a significant impact on customer prices.
	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 actual 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.
	Guarantees and Letters of Credit
	A summary of the face amount or maximum theoretical obligation under TECO Energy’s letters of credit and guarantees as of March 31, 2014 is as follows:
	Guarantees - TECO Energy
	(millions)						After(1)		Total		Liabilities Recognized
	Guarantees for the Benefit of:		2014		2015-2018		2018				at Mar. 31, 2014
	TECO Coal
	Fuel purchase related (2)		$	0.8	$	0.7	$	4	$	5.5	$	2.3
	Other subsidiaries
	Fuel purchase/energy management (2)			10		0		92.9		102.9		0.1
	Total		$	10.8	$	0.7	$	96.9	$	108.4	$	2.4
	Letters of Credit - Tampa Electric Company
	(millions)		2014		2015-2018		After(1)		Total		Liabilities Recognized
	Letters of Credit for the Benefit of:						2018				at Mar. 31, 2014
	Tampa Electric Company(2)		$	0	$	0	$	0.7	$	0.7	$	0.1
	Total		$	0	$	0	$	0.7	$	0.7	$	0.1
	-1	These letters of credit and guarantees renew annually and are shown on the basis that they will continue to renew beyond 2018.
	-2	The amounts shown are the maximum theoretical amounts guaranteed under current agreements. Liabilities recognized represent the associated obligation of TECO Energy under these agreements at March 31, 2014. The obligations under these letters of credit and guarantees include net accounts payable and net derivative liabilities.
	Financial Covenants
	In order to utilize their respective bank facilities, TECO Energy and its subsidiaries must meet certain financial tests, including a debt to capital ratio, as defined in the applicable agreements. In addition, TECO Energy, TECO Finance, TEC and the other operating companies have certain restrictive covenants in specific agreements and debt instruments. At March 31, 2014, TECO Energy, TECO Finance, TEC and the other operating companies were in compliance with all applicable financial covenants.
Tampa Electric Company [Member]	'
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 its 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. While the outcome of such proceedings is uncertain, management does not believe that their ultimate resolution will have a material adverse effect on the company’s results of operations, financial condition or cash flows.
	Legal Proceedings
	In November 2010, heavy equipment operated at a road construction site being conducted by Posen Construction, Inc. struck a natural gas line causing a rupture and ignition of the gas and an outage in the natural gas service to Lee and Collier counties, Florida. PGS filed suit in April 2011 against Posen Construction, Inc. in Federal Court for the Middle District of Florida to recover damages for repair and restoration relating to the incident and Posen Construction, Inc. counter-claimed against PGS alleging negligence. In the first quarter of 2014, the parties entered into a settlement agreement that resolves the claims of the parties. In addition, the suit filed in November 2011 by the Posen Construction, Inc. employee operating the heavy equipment involved in the incident in Lee County Circuit Court against PGS, Posen Construction, Inc. and a PGS contractor involved in the project, seeking damages for his injuries, also remains pending.
	In addition, three former or inactive TEC employees were maintaining a suit against TEC in Hillsborough County Circuit Court, Florida for personal injuries allegedly caused by exposure to a chemical substance at one of TEC’s power stations. The suit was originally filed in 2002, and the trial judge allowed the plaintiffs to seek punitive damages in connection with their case. In the first quarter of 2014 all plaintiffs voluntarily dismissed their suits with prejudice.
	TEC believes the claims in each of the pending actions described above in this item are without merit and intends to defend each matter vigorously. TEC is unable at this time to estimate the possible loss or range of loss with respect to these matters.
	Superfund and Former Manufactured Gas Plant Sites
	TEC, through its Tampa Electric and Peoples Gas divisions, is a PRP for certain superfund sites and, through its Peoples Gas division, for certain former manufactured gas plant sites. While the joint and several liability associated with these sites presents the potential for significant response costs, as of Dec. 31, 2013, TEC has estimated its ultimate financial liability to be $38.4 million, primarily at PGS. This amount has been accrued and is primarily reflected in the long-term liability section under “Other” on the Consolidated Balance Sheets. The environmental remediation costs associated with these sites, which are expected to be paid over many years, are not expected to have a significant impact on customer prices.
	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 actual 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.
	Guarantees and Letters of Credit
	A summary of the face amount or maximum theoretical obligation under TEC’s letters of credit as of March 31, 2014 is as follows:
	Letters of Credit - Tampa Electric Company
	(millions)						After (1)				Liabilities Recognized
	Letters of Credit for the Benefit of:		2014		2015-2018		2018		Total		at Mar. 31, 2014
	Tampa Electric Company (2)		$	0	$	0	$	0.7	$	0.7	$	0.1
	-1	These letters of credit renew annually and are shown on the basis that they will continue to renew beyond 2018.
	-2	The amounts shown are the maximum theoretical amounts guaranteed under current agreements. Liabilities recognized represent the associated obligation of TEC under these agreements at Mar. 31, 2014. The obligations under these letters of credit include net accounts payable and net derivative liabilities.
	Financial Covenants
	In order to utilize its bank credit facilities, TEC must meet certain financial tests, including a debt to capital ratio, as defined in the applicable agreements. In addition, TEC has certain restrictive covenants in specific agreements and debt instruments. At March 31, 2014, TEC was in compliance with all applicable financial covenants.

Segment_Information

Segment Information	3 Months Ended
	Mar. 31, 2014
Segment Information	'
	11. Segment Information
	TECO Energy is an electric and gas utility holding company with significant diversified activities. Segments are determined based on how management evaluates, measures and makes decisions with respect to the operations of the entity. The management of TECO Energy reports segments based on each subsidiary’s contribution of revenues, net income and total assets as required by the accounting guidance for disclosures about segments of an enterprise and related information. All significant intercompany transactions are eliminated in the Consolidated Condensed Financial Statements of TECO Energy, but are included in determining reportable segments.
	Segment Information (1)
	(millions)		Tampa		Peoples		TECO			Other &			TECO
	Three months ended Mar. 31,		Electric		Gas		Coal			Eliminations			Energy
	2014
	Revenues - external		$	452.9	$	122.4	$	106.1		$	2.7		$	684.1
	Sales to affiliates			0.3		0.2		0			(0.5	)		0
	Total revenues			453.2		122.6		106.1			2.2			684.1
	Depreciation and amortization			62.1		13.3		9			0.5			84.9
	Total interest charges(1)			22		3.4		1.5			14.2			41.1
	Internally allocated interest (1)			0		0		1.5			(1.5	)		0
	Provision (benefit) for income taxes			26.6		9.2		(2.2	)		(6.9	)		26.7
	Net income (loss) from continuing operations			45.2		14.6		(1.6	)		(11.2	)		47
	Income from discontinued operations, net			0		0		0			3.1			3.1
	Net income (loss)		$	45.2	$	14.6	($	1.6	)	($	8.1	)	$	50.1
	2013
	Revenues - external		$	417.8	$	121.9	$	117.9		$	3.5		$	661.1
	Sales to affiliates			0.2		0		0			(0.2	)		0
	Total revenues			418		121.9		117.9			3.3			661.1
	Depreciation and amortization			59		13		9.7			0.3			82
	Total interest charges(1)			23.4		3.4		1.7			13.9			42.4
	Internally allocated interest (1)			0		0		1.6			(1.6	)		0
	Provision (benefit) for income taxes			19.8		8.7		(0.1	)		(5.2	)		23.2
	Net income (loss) from continuing operations			31.8		13.8		3			(7.4	)		41.2
	Income from discontinued operations, net			0		0		0			0.3			0.3
	Net income (loss)		$	31.8	$	13.8	$	3		($	7.1	)	$	41.5
	At Mar. 31, 2014
	Total assets		$	6,120.80	$	1,031.10	$	319.5		($	40.7	)	$	7,430.70
	At Dec. 31, 2013
	Total assets		$	6,126.90	$	1,021.20	$	316.3		($	16.4	)	$	7,448.00
	-1	Segment net income is reported on a basis that includes internally allocated financing costs. Total interest charges include internally allocated interest costs that for January 2013 through March 2014 were at a pretax rate of 6.00% based on an average of each subsidiary’s equity and indebtedness to TECO Energy assuming a 50/50 debt/equity capital structure.
Tampa Electric Company [Member]	'
Segment Information	'
	9. Segment Information
	(millions)		Tampa		Peoples		Other &			Tampa Electric
	Three months ended Mar. 31,		Electric		Gas		Eliminations			Company
	2014
	Revenues - external		$	453.1	$	122.4	$	0		$	575.5
	Sales to affiliates			0.1		0.2		(0.3	)		0
	Total revenues			453.2		122.6		(0.3	)		575.5
	Depreciation and amortization			62.1		13.3		0			75.4
	Total interest charges			22		3.4		0			25.4
	Provision for income taxes			26.6		9.2		0			35.8
	Net income		$	45.2	$	14.6	$	0		$	59.8
	2013
	Revenues - external		$	417.9	$	121.9	$	0		$	539.8
	Sales to affiliates			0.1		0		(0.1	)		0
	Total revenues			418		121.9		(0.1	)		539.8
	Depreciation and amortization			59		13		0			72
	Total interest charges			23.4		3.4		0			26.8
	Provision for income taxes			19.8		8.7		0			28.5
	Net income		$	31.8	$	13.8	$	0		$	45.6
	Total assets at Mar. 31, 2014		$	5,871.00	$	999.4	($	5.1	)	$	6,865.30
	Total assets at Dec. 31, 2013		$	5,895.40	$	989.3	($	8.9	)	$	6,875.80

Accounting_for_Derivative_Inst

Accounting for Derivative Instruments and Hedging Activities	3 Months Ended
	Mar. 31, 2014
Accounting for Derivative Instruments and Hedging Activities	'
	12. Accounting for Derivative Instruments and Hedging Activities
	From time to time, TECO Energy and its affiliates enter into futures, forwards, swaps and option contracts for the following purposes:
		•		to limit the exposure to price fluctuations for physical purchases and sales of natural gas in the course of normal operations at Tampa Electric and PGS,
		•		to limit the exposure to interest rate fluctuations on debt securities at TECO Energy and its affiliates, and
		•		to limit the exposure to price fluctuations for physical purchases of fuel at TECO Coal.
	TECO Energy and its affiliates use derivatives only to reduce normal operating and market risks, not for speculative purposes. The company’s primary objective in using derivative instruments for regulated operations is to reduce the impact of market price volatility on ratepayers.
	The risk management policies adopted by TECO Energy provide a framework through which management monitors various risk exposures. Daily and periodic reporting of positions and other relevant metrics are performed by a centralized risk management group which is independent of all operating companies.
	The company applies the accounting standards for derivative instruments and hedging activities. These standards require companies to recognize derivatives as either assets or liabilities in the financial statements, to measure those instruments at fair value and to reflect the changes in the fair value of those instruments as either components of OCI or in net income, depending on the designation of those instruments. The changes in fair value that are recorded in OCI are not immediately recognized in current net income. As the underlying hedged transaction matures or the physical commodity is delivered, the deferred gain or loss on the related hedging instrument must be reclassified from OCI to earnings based on its value at the time of the instrument’s settlement. For effective hedge transactions, the amount reclassified from OCI to earnings is offset in net income by the market change of the amount paid or received on the underlying physical transaction.
	The company applies the accounting standards for regulated operations to financial instruments used to hedge the purchase of natural gas for its regulated companies. These standards, in accordance with the FPSC, permit the changes in fair value of natural gas derivatives to be recorded as regulatory assets or liabilities reflecting the impact of hedging activities on the fuel recovery clause. As a result, these changes are not recorded in OCI (see Note 3).
	A company’s physical contracts qualify for the NPNS exception to derivative accounting rules, provided they meet certain criteria. Generally, NPNS applies if the company deems the counterparty creditworthy, if the counterparty owns or controls resources within the proximity to allow for physical delivery of the commodity, if the company intends to receive physical delivery and if the transaction is reasonable in relation to the company’s business needs. As of March 31, 2014, all of the company’s physical contracts qualify for the NPNS exception.
	The following table presents the derivatives that are designated as cash flow hedges at March 31, 2014 and Dec. 31, 2013:
	Total Derivatives(1)
			Mar. 31,				Dec. 31,
	(millions)		2014				2013
	Current assets		$	15.6			$	9.7
	Long-term assets			0.2				0.3
	Total assets		$	15.8			$	10
	Current liabilities		$	0.1			$	0.1
	Long-term liabilities			0.1				0.2
	Total liabilities		$	0.2			$	0.3
	-1	Amounts presented above are on a gross basis, with asset and liability positions netted by counterparty in accordance with accounting standards for derivatives and hedging.
	The following table presents the gross amounts of derivatives and their related offset amounts as permitted by their respective master netting agreements at March 31, 2014 and Dec. 31, 2013. There was no collateral posted with or received from any counterparties.
	Offsetting of Derivative Assets and Liabilities
	(millions)
			Gross Amounts				Gross				Net Amounts of
			of Recognized				Amounts offset				Assets (Liabilities)
			Assets				on the Balance				Presented on the
			(Liabilities)				Sheet				Balance Sheet
	Mar. 31, 2014
	Description
	Derivative assets		$	16.1			$	(0.3	)		$	15.8
	Derivative liabilities		$	(0.5	)		$	0.3			$	(0.2	)
	Dec. 31, 2013
	Description
	Derivative assets		$	10.5			$	(0.5	)		$	10
	Derivative liabilities		$	(0.8	)		$	0.5			$	(0.3	)
	The following table presents the derivative hedges of diesel fuel contracts at March 31, 2014 and Dec. 31, 2013 to limit the exposure to changes in the market price for diesel fuel used in the production of coal:
	Diesel Fuel Derivatives
			Mar. 31,				Dec. 31,
	(millions)		2014				2013
	Current assets		$	0.1			$	0.2
	Long-term assets			0				0
	Total assets		$	0.1			$	0.2
	Current liabilities		$	0.1			$	0.1
	Long-term liabilities			0				0
	Total liabilities		$	0.1			$	0.1
	The following table presents the derivative hedges of natural gas contracts at March 31, 2014 and Dec. 31, 2013 to limit the exposure to changes in market price for natural gas used to produce energy and natural gas purchased for resale to customers:
	Natural Gas Derivatives
	(millions)		Mar. 31,				Dec. 31,
			2014				2013
	Current assets		$	15.5			$	9.5
	Long-term assets			0.2				0.3
	Total assets		$	15.7			$	9.8
	Current liabilities		$	0			$	0
	Long-term liabilities			0.1				0.2
	Total liabilities		$	0.1			$	0.2
	The ending balance in AOCI related to the cash flow hedges and interest rate swaps at March 31, 2014 is a net loss of $7.6 million after tax and accumulated amortization. This compares to a net loss of $7.8 million in AOCI after tax and accumulated amortization at Dec. 31, 2013.
	The following tables present the fair values and locations of derivative instruments recorded on the balance sheet at March 31, 2014 and Dec. 31, 2013:
	Derivatives Designated as Hedging Instruments
			Asset Derivatives								Liability Derivatives
	(millions)		Balance Sheet				Fair				Balance Sheet		Fair
	Mar. 31, 2014		Location				Value				Location		Value
	Commodity Contracts:
Diesel fuel derivatives:
Current			Derivative assets			$	0.1			Derivative liabilities		$	0.1
Long-term			Derivative assets				0			Derivative liabilities			0
Natural gas derivatives:
Current			Derivative assets				15.5			Derivative liabilities			0
Long-term			Derivative assets				0.2			Derivative liabilities			0.1
Total derivatives designated as hedging instruments						$	15.8					$	0.2
		Asset Derivatives								Liability Derivatives
(millions)		Balance Sheet				Fair				Balance Sheet				Fair
Dec. 31, 2013		Location				Value				Location				Value
Commodity Contracts:
Diesel fuel derivatives:
Current			Derivative assets			$	0.2				Derivative liabilities			$	0.1
Long-term			Derivative assets				0				Derivative liabilities				0
Natural gas derivatives:
Current			Derivative assets				9.5				Derivative liabilities				0
Long-term			Derivative assets				0.3				Derivative liabilities				0.2
Total derivatives designated as hedging instruments						$	10							$	0.3
The following tables present the effect of energy related derivatives on the fuel recovery clause mechanism in the Consolidated Condensed Balance Sheets as of March 31, 2014 and Dec. 31, 2013:
Energy Related Derivatives
		Asset Derivatives								Liability Derivatives
(millions)		Balance Sheet				Fair				Balance Sheet				Fair
Mar. 31, 2014		Location (1)				Value				Location (1)				Value
Commodity Contracts:
Natural gas derivatives:
Current			Regulatory liabilities			$	15.5				Regulatory assets			$	0
Long-term			Regulatory liabilities				0.2				Regulatory assets				0.1
Total						$	15.7							$	0.1
(millions)		Balance Sheet				Fair				Balance Sheet				Fair
Dec. 31, 2013		Location (1)				Value				Location (1)				Value
Commodity Contracts:
Natural gas derivatives:
Current			Regulatory liabilities			$	9.5				Regulatory assets			$	0
Long-term			Regulatory liabilities				0.3				Regulatory assets				0.2
Total						$	9.8							$	0.2
-1	Natural gas derivatives are deferred in accordance with accounting standards for regulated operations and all increases and decreases in the cost of natural gas supply are passed on to customers with the fuel recovery clause mechanism. As gains and losses are realized in future periods, they will be recorded as fuel costs in the Consolidated Condensed Statements of Income.
Based on the fair value of the instruments at March 31, 2014, net pretax gains of $15.5 million are expected to be reclassified from regulatory assets or liabilities to the Consolidated Condensed Statements of Income within the next 12 months.
The following table presents the effect of hedging instruments on OCI and income for the three months ended March 31:
		Amount of				Location of Gain/(Loss)		Amount of
		Gain/(Loss) on				Reclassified From AOCI		Gain/(Loss)
		Derivatives				Into Income		Reclassified
		Recognized in						From AOCI
(millions)		OCI						Into Income
Derivatives in Cash Flow Hedging Relationships			Effective						Effective
			Portion(1)						Portion(1)
2014
Interest rate contracts		$	0			Interest expense		($	0.2	)
Commodity contracts:
Diesel fuel derivatives			(0.1	)		Mining related costs			(0.1	)
Total		($	0.1	)				($	0.3	)
2013
Interest rate contracts		$	0			Interest expense		($	0.2	)
Commodity contracts:
Diesel fuel derivatives			0.2			Mining related costs			0
Total		$	0.2					($	0.2	)
-1	Changes in OCI and AOCI are reported in after-tax dollars.
For derivative instruments that meet cash flow hedge criteria, the effective portion of the gain or loss on the derivative is reported as a component of OCI and reclassified into earnings in the same period or period during which the hedged transaction affects earnings. Gains and losses on the derivatives representing either hedge ineffectiveness or hedge components excluded from the assessment of effectiveness are recognized in current earnings. For the three months ended March 31, 2014 and 2013, all hedges were effective.
The following table presents the derivative activity for instruments classified as qualifying cash flow hedges for the three months ended March 31:
		Fair Value				Amount of				Amount of
		Asset/				Gain/(Loss)				Gain/(Loss)
		(Liability)				Recognized				Reclassified From
(millions)						in OCI (1)				AOCI Into Income
2014
Interest rate swaps		$	0			$	0			($	0.2	)
Diesel fuel derivatives			0				(0.1	)			(0.1	)
Total		$	0			($	0.1	)		($	0.3	)
2013
Interest rate swaps		$	0			$	0			($	0.2	)
Diesel fuel derivatives			(0.6	)			0.2				0
Total		($	0.6	)		$	0.2			($	0.2	)
-1	Changes in OCI and AOCI are reported in after-tax dollars.
The maximum length of time over which the company is hedging its exposure to the variability in future cash flows extends to Dec. 31, 2014 for financial diesel fuel contracts and Dec. 31, 2016 for financial natural gas contracts. The following table presents by commodity type the company’s derivative volumes that, as of March 31, 2014, are expected to settle during the 2014, 2015 and 2016 fiscal years:
		Diesel Fuel Contracts								Natural Gas Contracts
(millions)		(Gallons)								(MMBTUs)
Year		Physical				Financial				Physical				Financial
2014			0				1.5				0				26.9
2015			0				0				0				18.5
2016			0				0				0				1.7
Total			0				1.5				0				47.1
The company is exposed to credit risk primarily through entering into derivative instruments with counterparties to limit its exposure to the commodity price fluctuations associated with diesel fuel and natural gas. Credit risk is the potential loss resulting from a counterparty’s nonperformance under an agreement. The company manages credit risk with policies and procedures for, among other things, counterparty analysis, exposure measurement and exposure monitoring and mitigation.
It is possible that volatility in commodity prices could cause the company to have material credit risk exposures with one or more counterparties. If such counterparties fail to perform their obligations under one or more agreements, the company could suffer a material financial loss. However, as of March 31, 2014, substantially all of the counterparties with transaction amounts outstanding in the company’s energy portfolio were rated investment grade by the major rating agencies. The company assesses credit risk internally for counterparties that are not rated.
The company has entered into commodity master arrangements with its counterparties to mitigate credit exposure to those counterparties. The company generally enters into the following master arrangements: (1) EEI agreements - standardized power sales contracts in the electric industry; (2) ISDA agreements - standardized financial gas and electric contracts; and (3) NAESB agreements - standardized physical gas contracts. The company believes that entering into such agreements reduces the risk from default by creating contractual rights relating to creditworthiness, collateral and termination.
The company has implemented procedures to monitor the creditworthiness of its counterparties and to consider nonperformance risk in determining the fair value of counterparty positions. Net liability positions are generally not adjusted as the company uses derivative transactions as hedges and has the ability and intent to perform under each of these contracts. In the instance of net asset positions, the company considers general market conditions and the observable financial health and outlook of specific counterparties in evaluating the potential impact of nonperformance risk to derivative positions. As of March 31, 2014, substantially all positions with counterparties were net assets.
Certain TECO Energy derivative instruments contain provisions that require the company’s debt, or in the case of derivative instruments where TEC is the counterparty, TEC’s debt, to maintain an investment grade credit rating from any or all of the major credit rating agencies. If debt ratings, including TEC’s, were to fall below investment grade, it could trigger these provisions, and the counterparties to the derivative instruments could request immediate payment or demand immediate and ongoing full overnight collateralization on derivative instruments in net liability positions. The company has no other contingent risk features associated with any derivative instruments.
The table below presents the fair value of the overall contractual contingent liability positions for the company’s derivative activity at March 31, 2014:
Contingent Features
		Fair Value				Derivative				Posted
		Asset/				Exposure				Collateral
(millions)		(Liability)				Asset/
At Mar. 31, 2014						(Liability)
Credit Rating		($	0.1	)		($	0.1	)		$	0
Tampa Electric Company [Member]	'
Accounting for Derivative Instruments and Hedging Activities	'
	10. Accounting for Derivative Instruments and Hedging Activities
	From time to time, TEC enters into futures, forwards, swaps and option contracts for the following purposes:
		•		to limit the exposure to price fluctuations for physical purchases and sales of natural gas in the course of normal operations, and
		•		to limit the exposure to interest rate fluctuations on debt securities.
	TEC uses derivatives only to reduce normal operating and market risks, not for speculative purposes. TEC’s primary objective in using derivative instruments for regulated operations is to reduce the impact of market price volatility on ratepayers.
	The risk management policies adopted by TEC provide a framework through which management monitors various risk exposures. Daily and periodic reporting of positions and other relevant metrics are performed by a centralized risk management group which is independent of all operating companies.
	TEC applies the accounting standards for derivatives and hedging. These standards require companies to recognize derivatives as either assets or liabilities in the financial statements, to measure those instruments at fair value and to reflect the changes in the fair value of those instruments as either components of OCI or in net income, depending on the designation of those instruments. The changes in fair value that are recorded in OCI are not immediately recognized in current net income. As the underlying hedged transaction matures or the physical commodity is delivered, the deferred gain or loss on the related hedging instrument must be reclassified from OCI to earnings based on its value at the time of the instrument’s settlement. For effective hedge transactions, the amount reclassified from OCI to earnings is offset in net income by the market change of the amount paid or received on the underlying physical transaction.
	TEC applies accounting standards for regulated operations to financial instruments used to hedge the purchase of natural gas for the regulated companies. These standards, in accordance with the FPSC, permit the changes in fair value of natural gas derivatives to be recorded as regulatory assets or liabilities reflecting the impact of hedging activities on the fuel recovery clause. As a result, these changes are not recorded in OCI (see Note 3).
	A company’s physical contracts qualify for the NPNS exception to derivative accounting rules, provided they meet certain criteria. Generally, NPNS applies if the company deems the counterparty creditworthy, if the counterparty owns or controls resources within the proximity to allow for physical delivery of the commodity, if the company intends to receive physical delivery and if the transaction is reasonable in relation to the company’s business needs. As of March 31, 2014, all of TEC’s physical contracts qualify for the NPNS exception.
	The following table presents the derivative hedges of natural gas contracts at March 31, 2014 and Dec. 31, 2013 to limit the exposure to changes in the market price for natural gas used to produce energy and natural gas purchased for resale to customers:
	Natural Gas Derivatives
			Mar. 31,				Dec. 31,
	(millions)		2014				2013
	Current assets		$	15.5			$	9.5
	Long-term assets			0.2				0.3
	Total assets		$	15.7			$	9.8
	Current liabilities (1)		$	0			$	0
	Long-term liabilities			0.1				0.2
	Total liabilities		$	0.1			$	0.2
	-1	Amounts presented above are on a gross basis, with asset and liability positions netted by counterparty in accordance with accounting standards for derivatives and hedging.
	The ending balance in AOCI related to previously settled interest rate swaps at March 31, 2014 is a net loss of $7.6 million after tax and accumulated amortization. This compares to a net loss of $7.8 million in AOCI after tax and accumulated amortization at Dec. 31, 2013.
	The following table presents the gross amounts of derivatives and their related offset amounts as permitted by their respective master netting agreements at March 31, 2014 and Dec. 31, 2013. There was no collateral posted with or received from any counterparties:
	Offsetting of Derivative Assets and Liabilities
			Gross Amounts				Gross Amounts				Net Amounts of
			of Recognized				offset on the				Assets (Liabilities)
			Assets				Balance Sheet				Presented on the
	(millions)		(Liabilities)								Balance Sheet
	Mar. 31, 2014
	Description
	Derivative assets		$	16			$	(0.3	)		$	15.7
	Derivative liabilities		$	(0.4	)		$	0.3			$	(0.1	)
	Dec. 31, 2013
	Description
	Derivative assets		$	10.3			$	(0.5	)		$	9.8
	Derivative liabilities		$	(0.7	)		$	0.5			$	(0.2	)
	The following table presents the effect of energy related derivatives on the fuel recovery clause mechanism in the Consolidated Condensed Balance Sheets as of March 31, 2014 and Dec. 31, 2013:
	Energy Related Derivatives
			Asset Derivatives						Liability Derivatives
	(millions)		Balance Sheet		Fair				Balance Sheet		Fair
	Mar. 31, 2014		Location (1)		Value				Location (1)		Value
	Commodity Contracts:
	Natural gas derivatives:
	Current		Regulatory liabilities		$	15.5			Regulatory assets		$	0
	Long-term		Regulatory liabilities			0.2			Regulatory assets			0.1
	Total				$	15.7					$	0.1
	(millions)		Balance Sheet		Fair				Balance Sheet		Fair
	Dec. 31, 2013		Location (1)		Value				Location (1)		Value
	Commodity Contracts:
	Natural gas derivatives:
	Current		Regulatory liabilities		$	9.5			Regulatory assets		$	0
	Long-term		Regulatory liabilities			0.3			Regulatory assets			0.2
	Total				$	9.8					$	0.2
	-1	Natural gas derivatives are deferred in accordance with accounting standards for regulated operations and all increases and decreases in the cost of natural gas supply are passed on to customers with the fuel recovery clause mechanism. As gains and losses are realized in future periods, they will be recorded as fuel costs in the Consolidated Condensed Statements of Income.
	Based on the fair value of the instruments at March 31, 2014, net pretax losses of $15.5 million are expected to be reclassified from regulatory assets to the Consolidated Condensed Statements of Income within the next 12 months.
	The following table presents the effect of hedging instruments on OCI and income for the three months ended March 31:
	(millions)		Amount of				Location of Gain/(Loss)		Amount of
			Gain/(Loss) on				Reclassified From AOCI		Gain/(Loss)
			Derivatives				Into Income		Reclassified
			Recognized in						From AOCI
			OCI						Into Income
	Derivatives in Cash Flow Hedging Relationships			Effective						Effective
										Portion	(1)
				Portion	(1)
2014
Interest rate contracts		$	0			Interest expense		($	0.2	)
Total		$	0					($	0.2	)
2013
Interest rate contracts		$	0			Interest expense		($	0.2	)
Total		$	0					($	0.2	)
-1	Changes in OCI and AOCI are reported in after-tax dollars.
For derivative instruments that meet cash flow hedge criteria, the effective portion of the gain or loss on the derivative is reported as a component of OCI and reclassified into earnings in the same period or period during which the hedged transaction affects earnings. Gains and losses on the derivatives representing either hedge ineffectiveness or hedge components excluded from the assessment of effectiveness are recognized in current earnings. For the three months ended March 31, 2014 and 2013, all hedges were effective.
The maximum length of time over which TEC is hedging its exposure to the variability in future cash flows extends to Dec. 31, 2016 for the financial natural gas contracts. The following table presents by commodity type TEC’s derivative volumes that, as of March 31, 2014, are expected to settle during the 2014, 2015 and 2016 fiscal years:
		Natural Gas Contracts
(millions)		(MMBTUs)
Year		Physical				Financial
2014			0				26.9
2015			0				18.5
2016			0				1.7
Total			0				47.1
TEC is exposed to credit risk primarily through entering into derivative instruments with counterparties to limit its exposure to the commodity price fluctuations associated with natural gas. Credit risk is the potential loss resulting from a counterparty’s nonperformance under an agreement. TEC manages credit risk with policies and procedures for, among other things, counterparty analysis, exposure measurement and exposure monitoring and mitigation.
It is possible that volatility in commodity prices could cause TEC to have material credit risk exposures with one or more counterparties. If such counterparties fail to perform their obligations under one or more agreements, TEC could suffer a material financial loss. However, as of March 31, 2014, substantially all of the counterparties with transaction amounts outstanding in TEC’s energy portfolio were rated investment grade by the major rating agencies. TEC assesses credit risk internally for counterparties that are not rated.
TEC has entered into commodity master arrangements with its counterparties to mitigate credit exposure to those counterparties. TEC generally enters into the following master arrangements: (1) EEI agreements- standardized power sales contracts in the electric industry; (2) ISDA agreements- standardized financial gas and electric contracts; and (3) NAESB agreements - standardized physical gas contracts. TEC believes that entering into such agreements reduces the risk from default by creating contractual rights relating to creditworthiness, collateral and termination.
TEC has implemented procedures to monitor the creditworthiness of its counterparties and to consider nonperformance risk in determining the fair value of counterparty positions. Net liability positions are generally not adjusted as TEC uses derivative transactions as hedges and has the ability and intent to perform under each of these contracts. In the instance of net asset positions, TEC considers general market conditions and the observable financial health and outlook of specific counterparties in evaluating the potential impact of nonperformance risk to derivative positions. As of March 31, 2014, substantially all positions with counterparties were net assets.
Certain TEC derivative instruments contain provisions that require TEC’s debt to maintain an investment grade credit rating from any or all of the major credit rating agencies. If debt ratings were to fall below investment grade, it could trigger these provisions, and the counterparties to the derivative instruments could request immediate payment or demand immediate and ongoing full overnight collateralization on derivative instruments in net liability positions. TEC has no other contingent risk features associated with any derivative instruments. Substantially all of TEC’s open positions with counterparties as of March 31, 2014 were asset positions.

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2014
Fair Value Measurements	'
	13. Fair Value Measurements
	Items Measured at Fair Value on a Recurring Basis
	The following tables set forth by level within the fair value hierarchy the company’s financial assets and liabilities that were accounted for at fair value on a recurring basis as of March 31, 2014 and Dec. 31, 2013. As required by accounting standards for fair value measurements, financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The company’s assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy levels. For natural gas and diesel fuel swaps, the market approach was used in determining fair value.
	Recurring Fair Value Measures
		At fair value as of Mar. 31, 2014
	(millions)	Level 1		Level 2		Level 3		Total
	Assets
	Natural gas swaps	$	0	$	15.7	$	0	$	15.7
	Diesel fuel swaps		0		0.1		0		0.1
	Total	$	0	$	15.8	$	0	$	15.8
	Liabilities
	Natural gas swaps	$	0	$	0.1	$	0	$	0.1
	Diesel fuel swaps		0		0.1		0		0.1
	Total	$	0	$	0.2	$	0	$	0.2
		At fair value as of Dec. 31, 2013
	(millions)	Level 1		Level 2		Level 3		Total
	Assets
	Natural gas swaps	$	0	$	9.8	$	0	$	9.8
	Diesel fuel swaps		0		0.2		0		0.2
	Total	$	0	$	10	$	0	$	10
	Liabilities
	Natural gas swaps	$	0	$	0.2	$	0	$	0.2
	Diesel fuel swaps		0		0.1		0		0.1
	Total	$	0	$	0.3	$	0	$	0.3
	Natural gas and diesel fuel swaps are OTC swap instruments. The primary pricing inputs in determining the fair value of these swaps are the NYMEX quoted closing prices of exchange-traded instruments. These prices are applied to the notional amounts of active positions to determine the reported fair value (see Note 12).
	The company considered the impact of nonperformance risk in determining the fair value of derivatives. The company considered the net position with each counterparty, past performance of both parties, the intent of the parties, indications of credit deterioration and whether the markets in which the company transacts have experienced dislocation. At March 31, 2014, the fair value of derivatives was not materially affected by nonperformance risk. There were no Level 3 assets or liabilities for the periods presented.
Tampa Electric Company [Member]	'
Fair Value Measurements	'
	11. Fair Value Measurements
	Items Measured at Fair Value on a Recurring Basis
	The following tables set forth by level within the fair value hierarchy TEC’s financial assets and liabilities that were accounted for at fair value on a recurring basis as of March 31, 2014 and Dec. 31, 2013. As required by accounting standards for fair value measurements, financial assets and liabilities are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. TEC’s assessment of the significance of a particular input to the fair value measurement requires judgment, and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy levels. For all assets and liabilities presented below, the market approach was used in determining fair value.
	Recurring Derivative Fair Value Measures
		At fair value as of Mar. 31, 2014
	(millions)	Level 1		Level 2		Level 3		Total
	Assets
	Natural gas swaps	$	0	$	15.7	$	0	$	15.7
	Total	$	0	$	15.7	$	0	$	15.7
	Liabilities
	Natural gas swaps	$	0	$	0.1	$	0	$	0.1
	Total	$	0	$	0.1	$	0	$	0.1
		At fair value as of Dec. 31, 2013
	(millions)	Level 1		Level 2		Level 3		Total
	Assets
	Natural gas swaps	$	0	$	9.8	$	0	$	9.8
	Total	$	0	$	9.8	$	0	$	9.8
	Liabilities
	Natural gas swaps	$	0	$	0.2	$	0	$	0.2
	Total	$	0	$	0.2	$	0	$	0.2
	Natural gas swaps are OTC swap instruments. The primary pricing inputs in determining the fair value of natural gas swaps are the NYMEX quoted closing prices of exchange-traded instruments. These prices are applied to the notional amounts of active positions to determine the reported fair value (see Note 10).
	TEC considered the impact of nonperformance risk in determining the fair value of derivatives. TEC considered the net position with each counterparty, past performance of both parties, the intent of the parties, indications of credit deterioration and whether the markets in which TEC transacts have experienced dislocation. At March 31, 2014, the fair value of derivatives was not materially affected by nonperformance risk. There were no Level 3 assets or liabilities for the periods presented.

Variable_Interest_Entities

Variable Interest Entities	3 Months Ended
	Mar. 31, 2014
Variable Interest Entities	'
	14. Variable Interest Entities
	In the determination of a VIE’s primary beneficiary, the primary beneficiary is the enterprise that has both 1) the power to direct the activities of a VIE that most significantly impact the entity’s economic performance and 2) the obligation to absorb losses of the entity that could potentially be significant to the VIE or the right to receive benefits from the entity that could potentially be significant to the VIE.
	TEC has entered into multiple PPAs with wholesale energy providers in Florida to ensure the ability to meet customer energy demand and to provide lower cost options in the meeting of this demand. These agreements range in size from 117 MW to 160 MW of available capacity, are with similar entities and contain similar provisions. Because some of these provisions provide for the transfer or sharing of a number of risks inherent in the generation of energy, these agreements meet the definition of being VIEs. These risks include: operating and maintenance, regulatory, credit, commodity/fuel and energy market risk. TEC has reviewed these risks and has determined that the owners of these entities have retained the majority of these risks over the expected life of the underlying generating assets, have the power to direct the most significant activities, the obligation or right to absorb losses or benefits and hence remain the primary beneficiaries. As a result, TEC is not required to consolidate any of these entities. TEC purchased $5.9 million and $4.9 million of capacity pursuant to PPAs for the three months ended March 31, 2014 and 2013, respectively.
	The company does not provide any material financial or other support to any of the VIEs it is involved with, nor is the company under any obligation to absorb losses associated with these VIEs. In the normal course of business, the company’s involvement with these VIEs does not affect its Consolidated Condensed Balance Sheets, Statements of Income or Cash Flows.
Tampa Electric Company [Member]	'
Variable Interest Entities	'
	13. Variable Interest Entities
	In the determination of a VIE’s primary beneficiary, the primary beneficiary is the enterprise that has both 1) the power to direct the activities of a VIE that most significantly impact the entity’s economic performance and 2) the obligation to absorb losses of the entity that could potentially be significant to the VIE or the right to receive benefits from the entity that could potentially be significant to the VIE.
	TEC has entered into multiple PPAs with wholesale energy providers in Florida to ensure the ability to meet customer energy demand and to provide lower cost options in the meeting of this demand. These agreements range in size from 117 MW to 160 MW of available capacity, are with similar entities and contain similar provisions. Because some of these provisions provide for the transfer or sharing of a number of risks inherent in the generation of energy, these agreements meet the definition of being VIEs. These risks include: operating and maintenance, regulatory, credit, commodity/fuel and energy market risk. TEC has reviewed these risks and has determined that the owners of these entities have retained the majority of these risks over the expected life of the underlying generating assets, have the power to direct the most significant activities, the obligation or right to absorb losses or benefits and hence remain the primary beneficiaries. As a result, TEC is not required to consolidate any of these entities. TEC purchased $5.9 million and $4.9 million of capacity pursuant to PPAs for the three months ended March 31, 2014 and 2013, respectively.
	TEC does not provide any material financial or other support to any of the VIEs it is involved with, nor is TEC under any obligation to absorb losses associated with these VIEs. In the normal course of business, TEC’s involvement with these VIEs does not affect its Consolidated Condensed Balance Sheets, Statements of Income or Cash Flows.

Discontinued_Operations

Discontinued Operations	3 Months Ended
	Mar. 31, 2014
Discontinued Operations And Disposal Groups [Abstract]	'
Discontinued Operations	'
	15. Discontinued Operations
	In 2012, TECO Guatemala completed the sale of its interests in the Alborada and San José power stations, and related solid fuel handling and port facilities in Guatemala. All periods have been adjusted to reflect the reclassification of results from operations to discontinued operations for TECO Guatemala and certain charges at Parent that directly relate to TECO Guatemala. Additionally, in March 2014, an indemnification provision for an uncertain tax position at TCAE that was provided for in the 2012 purchase agreement was reversed due to favorable final decision by the highest court in Guatemala, resulting in the income from operations amount shown in the table below. The following table provides selected components of discontinued operations:
	Components of income from discontinued operations
	(millions)
	Three months ended Mar. 31,	2014		2013
	Revenues	$	0	$	0
	Income from operations		5		0.4
	Income from discontinued operations		5		0.4
	Provision for income taxes		1.9		0.1
	Income from discontinued operations, net	$	3.1	$	0.3

Subsequent_Events

Subsequent Events	3 Months Ended
	Mar. 31, 2014
Subsequent Events [Abstract]	'
Subsequent Events	'
	16. Subsequent Events
	Pending Acquisition of New Mexico Gas Company
	As previously disclosed, TECO Energy must obtain approval for the acquisition from the NMPRC prior to closing the transaction. Hearings before the hearing examiner were concluded on April 3, 2014.
	The current schedule calls for the parties to submit post-hearing briefs on May 2, 2014, with reply briefs due May 15, 2014. Following the submittal of briefs, the hearing examiner will provide a recommendation to the NMPRC. The schedule for the hearing examiner’s recommendation and the NMPRC’s final decision has not been established but we expect to close the transaction by mid to late third quarter this year.
	TECO Guatemala Holdings, LLC v. The Republic of Guatemala
	As previously reported, on Dec. 19, 2013, the ICSID Tribunal hearing the arbitration claim of TGH, a wholly owned subsidiary of TECO Energy, Inc., against the Republic of Guatemala (“Guatemala”) under the DR – CAFTA, issued an award in the case (the “Award”). The ICSID Tribunal unanimously found in favor of TGH and awarded damages to TGH of approximately U.S. $21.1 million, plus interest from Oct. 21, 2010 at a rate equal to the U.S. prime rate plus 2%. In addition, the Tribunal ruled that Guatemala must reimburse TGH for approximately U.S. $7.5 million of the costs that it incurred in pursuing the arbitration. Pursuant to ICSID’s rules and procedures, each party had 120 days after the date of the Award to file an application for its annulment.
	On April 18, 2014, Guatemala filed an application for annulment of the entire Award (or, alternatively, certain parts of the Award) pursuant to applicable ICSID rules. Guatemala also requested that the enforcement of the Award be stayed while the annulment proceeding is pending. Under the applicable rules, the enforcement of the Award is provisionally stayed until the ad hoc committee that will be deciding Guatemala’s application is constituted and makes a decision regarding whether the stay should continue through the rest of the annulment proceeding.
	Also on April 18, 2014, TGH separately filed an application for partial annulment of the Award on the basis of certain deficiencies in the Tribunal’s determination of the amount of TGH’s damages. If TGH’s application is successful, TGH will be able to seek additional damages from Guatemala in a new arbitration proceeding.
	While the duration of the annulment proceedings is uncertain, they are expected to take approximately 17 to 24 months to conclude. Pending the outcome of annulment proceedings, results in the first quarter of 2014 do not reflect any benefit of this decision.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2014
Principles of Consolidation and Basis of Presentation	'
	Principles of Consolidation and Basis of Presentation
	The consolidated condensed financial statements include the accounts of TECO Energy, Inc., its majority-owned and controlled subsidiaries and the accounts of VIEs for which it is the primary beneficiary (TECO Energy or the company). TECO Energy is considered to be the primary beneficiary of VIEs if it has both 1) the power to direct the activities of a VIE that most significantly impact the entity’s economic performance and 2) the obligation to absorb losses of the entity that could potentially be significant to the VIE or the right to receive benefits from the entity that could potentially be significant to the VIE. For the periods presented, no VIEs have been consolidated in continuing operations (see Note 14).
	All significant intercompany balances and intercompany transactions 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 TECO Energy, Inc. and its subsidiaries as of March 31, 2014 and Dec. 31, 2013, and the results of operations and cash flows for the periods ended March 31, 2014 and 2013. The results of operations for the three months ended March 31, 2014 are not necessarily indicative of the results that can be expected for the entire fiscal year ending Dec. 31, 2014.
	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 data 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.
Revenues	'
	Revenues
	As of March 31, 2014 and Dec. 31, 2013, unbilled revenues of $48.1 million and $46.7 million, respectively, are included in the “Receivables” line item on the Consolidated Condensed Balance Sheets.
Accounting for Excise Taxes, Franchise Fees and Gross Receipts	'
	Accounting for Excise Taxes, Franchise Fees and Gross Receipts
	TECO Coal incurs most of TECO Energy’s total excise taxes, which are accrued as an expense and reconciled to the actual cash payment of excise taxes. As general expenses, they are not specifically recovered through revenues. Excise taxes paid by the regulated utilities are not material and are expensed when incurred.
	The regulated utilities are allowed to recover certain costs on a dollar-per-dollar basis incurred from customers through prices 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 the regulated utilities are included as an expense on the Consolidated Condensed Statements of Income in “Taxes, other than income”. These amounts totaled $27.2 million and $25.4 million for the three months ended March 31, 2014 and 2013, respectively.
Cash Flows Related to Derivatives and Hedging Activities	'
	Cash Flows Related to Derivatives and Hedging Activities
	The company classifies cash inflows and outflows related to derivative and hedging instruments in the appropriate cash flow sections associated with the item being hedged. In the case of diesel fuel swaps, which are used to mitigate the fluctuations in the price of diesel fuel, the cash inflows and outflows are included in the operating section. For natural gas and ongoing interest rate swaps, the cash inflows and outflows are included in the operating section. For interest rate swaps that settle coincident with the debt issuance, the cash inflows and outflows are treated as premiums or discounts and included in the financing section of the Consolidated Condensed Statements of Cash Flows.
Reclassifications	'
	Reclassifications
	Certain reclassifications were made to prior year amounts to conform to current period presentation. None of the reclassifications affected TECO Energy’s net income in any period.
Tampa Electric Company [Member]	'
Principles of Consolidation and Basis of Presentation	'
	Principles of Consolidation and Basis of Presentation
	TEC is a wholly-owned subsidiary of TECO Energy, Inc. For the purposes of its consolidated financial reporting, TEC is comprised of the electric division, generally referred to as Tampa Electric, the natural gas division, generally referred to as PGS, and potentially the accounts of VIEs for which it is the primary beneficiary. For the periods presented, no VIEs have been consolidated (see Note 13).
	All significant intercompany balances and intercompany transactions 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 March 31, 2014 and Dec. 31, 2013, and the results of operations and cash flows for the periods ended March 31, 2014 and 2013. The results of operations for the three months ended March 31, 2014 are not necessarily indicative of the results that can be expected for the entire fiscal year ending Dec. 31, 2014.
	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 data 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.
Revenues	'
	Revenues
	As of March 31, 2014 and Dec. 31, 2013, unbilled revenues of $48.1 million and $46.7 million, respectively, are included in the “Receivables” line item on the Consolidated Condensed Balance Sheets.
Accounting for Excise Taxes, Franchise Fees and Gross Receipts	'
	Accounting for Franchise Fees and Gross Receipts
	The regulated utilities are allowed to recover certain costs on a dollar-per-dollar basis incurred from customers through prices 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 the regulated utilities are included as an expense on the Consolidated Condensed Statements of Income in “Taxes, other than income”. These amounts totaled $27.2 million and $25.4 million for the three months ended March 31, 2014 and 2013, respectively.
Cash Flows Related to Derivatives and Hedging Activities	'
	Cash Flows Related to Derivatives and Hedging Activities
	TEC classifies cash inflows and outflows related to derivative and hedging instruments in the appropriate cash flow sections associated with the item being hedged. For natural gas and ongoing interest rate swaps, the cash inflows and outflows are included in the operating section. For interest rate swaps that settle coincident with the debt issuance, the cash inflows and outflows are treated as premiums or discounts and included in the financing section of the Consolidated Condensed Statements of Cash Flows.
Reclassifications	'
	Reclassifications
	Certain reclassifications were made to prior year amounts to conform to current period presentation. Income tax expense related to regulated operations was previously included within income from operations as it is part of the determination of utility revenue requirements. Income tax expense is now presented directly above net income to conform to the TECO Energy, Inc. presentation. For prior periods, this change results in an increase in income from operations for the amount of income tax expense reclassified. None of the reclassifications affected TEC’s net income in any period.

Regulatory_Tables

Regulatory (Tables)	3 Months Ended
	Mar. 31, 2014
Schedule of Regulatory Assets and Regulatory Liabilities	'
	Details of the regulatory assets and liabilities as of March 31, 2014 and Dec. 31, 2013 are presented in the following table:
	Regulatory Assets and Liabilities
	(millions)		Mar. 31,		Dec. 31,
			2014		2013
	Regulatory assets:
	Regulatory tax asset (1)		$	67.9	$	67.4
	Other:
	Cost-recovery clauses			3.3		6.1
	Postretirement benefit asset			180.2		182.7
	Deferred bond refinancing costs (2)			7.8		8
	Environmental remediation			51.4		51.4
	Competitive rate adjustment			3.4		4.1
	Other			7.5		7.7
	Total other regulatory assets			253.6		260
	Total regulatory assets			321.5		327.4
	Less: Current portion			32.7		34.3
	Long-term regulatory assets		$	288.8	$	293.1
	Regulatory liabilities:
	Regulatory tax liability (1)		$	5.8	$	9.8
	Other:
	Cost-recovery clauses			58.9		54.5
	Transmission and delivery storm reserve			56.1		56.1
	Deferred gain on property sales (3)			1.7		2
	Provision for stipulation and other			0.8		0.8
	Accumulated reserve—cost of removal			591.8		594
	Total other regulatory liabilities			709.3		707.4
	Total regulatory liabilities			715.1		717.2
	Less: Current portion			90.1		85.8
	Long-term regulatory liabilities		$	625	$	631.4
	-1	Primarily related to plant life and derivative positions.
	-2	Amortized over the term of the related debt instruments.
	-3	Amortized over a 5-year period with various ending dates.
Regulatory Assets and Related Recovery Period	'
	All regulatory assets are recovered through the regulatory process. The following table further details the regulatory assets and the related recovery periods:
	Regulatory Assets
			Mar. 31,		Dec. 31,
	(millions)		2014		2013
	Clause recoverable (1)		$	6.7	$	10.2
	Components of rate base (2)			183.2		185.6
	Regulatory tax assets (3)			67.9		67.4
	Capital structure and other (3)			63.7		64.2
	Total		$	321.5	$	327.4
	-1	To be recovered through cost-recovery clauses approved by the FPSC on a dollar-for-dollar basis in the next year.
	-2	Primarily reflects allowed working capital, which is included in rate base and earns a rate of return as permitted by the FPSC.
	-3	“Regulatory tax assets” and “Capital structure and other” regulatory assets have a recoverable period longer than a fiscal year and are recognized over the period authorized by the regulatory agency. Also included are unamortized loan costs, which are amortized over the life of the related debt instruments. See footnotes 1 and 2 in the prior table for additional information.
Tampa Electric Company [Member]	'
Schedule of Regulatory Assets and Regulatory Liabilities	'
	Details of the regulatory assets and liabilities as of March 31, 2014 and Dec. 31, 2013 are presented in the following table:
	Regulatory Assets and Liabilities
	(millions)		Mar. 31,		Dec. 31,
			2014		2013
	Regulatory assets:
	Regulatory tax asset (1)		$	67.9	$	67.4
	Other:
	Cost-recovery clauses			3.3		6.1
	Postretirement benefit asset			180.2		182.7
	Deferred bond refinancing costs (2)			7.8		8
	Environmental remediation			51.4		51.4
	Competitive rate adjustment			3.4		4.1
	Other			7.5		7.7
	Total other regulatory assets			253.6		260
	Total regulatory assets			321.5		327.4
	Less: Current portion			32.7		34.3
	Long-term regulatory assets		$	288.8	$	293.1
	Regulatory liabilities:
	Regulatory tax liability (1)		$	5.8	$	9.8
	Other:
	Cost-recovery clauses			58.9		54.5
	Transmission and delivery storm reserve			56.1		56.1
	Deferred gain on property sales (3)			1.7		2
	Provision for stipulation and other			0.8		0.8
	Accumulated reserve—cost of removal			591.8		594
	Total other regulatory liabilities			709.3		707.4
	Total regulatory liabilities			715.1		717.2
	Less: Current portion			90.1		85.8
	Long-term regulatory liabilities		$	625	$	631.4
	-1	Primarily related to plant life and derivative positions.
	-2	Amortized over the term of the related debt instruments.
	-3	Amortized over a 5-year period with various ending dates.
Regulatory Assets and Related Recovery Period	'
	All regulatory assets are recovered through the regulatory process. The following table further details the regulatory assets and the related recovery periods:
	Regulatory Assets
	(millions)		Mar. 31,		Dec. 31,
			2014		2013
	Clause recoverable (1)		$	6.7	$	10.2
	Components of rate base (2)			183.2		185.6
	Regulatory tax assets (3)			67.9		67.4
	Capital structure and other (3)			63.7		64.2
	Total		$	321.5	$	327.4
	-1	To be recovered through cost-recovery clauses approved by the FPSC on a dollar-for-dollar basis in the next year.
	-2	Primarily reflects allowed working capital, which is included in rate base and earns a rate of return as permitted by the FPSC.
	-3	“Regulatory tax assets” and “Capital structure and other” regulatory assets have a recoverable period longer than a fiscal year and are recognized over the period authorized by the regulatory agency. Also included are unamortized loan costs, which are amortized over the life of the related debt instruments. See footnotes 1 and 2 in the prior table for additional information.

Employee_Postretirement_Benefi1

Employee Postretirement Benefits (Tables)	3 Months Ended
	Mar. 31, 2014
Compensation And Retirement Disclosure [Abstract]	'
Schedule of Net Periodic Benefit Cost	'
	Included in the table below is the periodic expense for pension and other postretirement benefits offered by the company.
	Pension Expense
	(millions)	Pension Benefits						Other Postretirement Benefits
	Three months ended Mar. 31,	2014			2013			2014		2013
	Components of net periodic benefit expense
	Service cost	$	4.1		$	4.8		$	0.6	$	0.7
	Interest cost on projected benefit obligations		8.2			7.2			2.6		2.3
	Expected return on assets		(10.3	)		(9.7	)		0		0
	Amortization of:
	Prior service cost		(0.1	)		(0.1	)		0		(0.1	)
	Actuarial loss		3.2			5			0		0.3
	Net pension expense recognized in the Consolidated Condensed Statements of Income	$	5.1		$	7.2		$	3.2	$	3.2

ShortTerm_Debt_Tables

Short-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2014
Short-Term Debt Credit Facilities	'
	At March 31, 2014 and Dec. 31, 2013, the following credit facilities and related borrowings existed:
	Credit Facilities
			Mar. 31, 2014						Dec. 31, 2013
	(millions)		Credit		Borrowings		Letters of		Credit		Borrowings		Letters of
			Facilities		Outstanding (1)		Credit		Facilities		Outstanding (1)		Credit
							Outstanding						Outstanding
	Tampa Electric Company:
	5-year facility (2)		$	325	$	0	$	0.7	$	325	$	6	$	0.7
	1-year accounts receivable facility			150		29		0		150		78		0
	TECO Energy/TECO Finance:
	5-year facility (2)(3)			200		0		0		200		0		0
	Total		$	675	$	29	$	0.7	$	675	$	84	$	0.7
	-1	Borrowings outstanding are reported as notes payable.
	-2	This 5-year facility matures Dec. 17, 2018.
	-3	TECO Finance is the borrower and TECO Energy is the guarantor of this facility.
Tampa Electric Company [Member]	'
Short-Term Debt Credit Facilities	'
	At March 31, 2014 and Dec. 31, 2013, the following credit facilities and related borrowings existed:
	Credit Facilities
			Mar. 31, 2014						Dec. 31, 2013
	(millions)		Credit		Borrowings		Letters of		Credit		Borrowings		Letters of
			Facilities		Outstanding (1)		Credit		Facilities		Outstanding (1)		Credit
							Outstanding						Outstanding
	Tampa Electric Company:
	5-year facility (2)		$	325	$	0	$	0.7	$	325	$	6	$	0.7
	1-year accounts receivable facility			150		29		0		150		78		0
	Total		$	475	$	29	$	0.7	$	475	$	84	$	0.7
	-1	Borrowings outstanding are reported as notes payable.
	-2	This 5-year facility matures Dec. 17, 2018.

Other_Comprehensive_Income_Tab

Other Comprehensive Income (Tables)	3 Months Ended
	Mar. 31, 2014
Other Comprehensive Income	'
	TECO Energy reported the following OCI for the three months ended March 31, 2014 and 2013, related to changes in the fair value of cash flow hedges and amortization of unrecognized benefit costs associated with the company’s postretirement plans:
	Other Comprehensive Income
			Three months ended Mar. 31,
	(millions)		Gross			Tax			Net
	2014
	Unrealized loss on cash flow hedges		($	0.1	)	$	0		($	0.1	)
	Reclassification from AOCI to net income (1)			0.4			(0.1	)		0.3
	Gain on cash flow hedges			0.3			(0.1	)		0.2
	Amortization of unrecognized benefit costs (2)			0.8			(0.3	)		0.5
	Increase in unrecognized post employment costs (3)			(12.9	)		4.7			(8.2	)
	Total other comprehensive loss		($	11.8	)	$	4.3		($	7.5	)
	2013
	Unrealized gain on cash flow hedges		$	0.3		($	0.1	)	$	0.2
	Reclassification from AOCI to net income (1)			0.3			(0.1	)		0.2
	Gain on cash flow hedges			0.6			(0.2	)		0.4
	Amortization of unrecognized benefit costs (2)			1.1			(0.4	)		0.7
	Total other comprehensive income		$	1.7		($	0.6	)	$	1.1
	-1	Related to interest rate contracts recognized in Interest expense and commodity contracts recognized in Mining related costs.
	-2	Related to postretirement benefits. See Note 5 for additional information.
	-3	Amount reflects an out-of-period adjustment to unfunded black lung liability.
Accumulated Other Comprehensive Loss	'
	Accumulated Other Comprehensive Loss
	(millions)		Mar. 31, 2014			Dec. 31, 2013
	Unrecognized pension loss and prior service credit (1)		($	20	)	($	20.5	)
	Unrecognized other benefit loss, prior service cost and transition obligation (2)			6.9			15.1
	Net unrealized losses from cash flow hedges (3)			(7.6	)		(7.8	)
	Total accumulated other comprehensive loss		($	20.7	)	($	13.2	)
	-1	Net of tax benefit of $12.3 million and $12.6 million as of Mar. 31, 2014 and Dec. 31, 2013, respectively.
	-2	Net of tax expense of $4.4 million and $9.1 million as of Mar. 31, 2014 and Dec. 31, 2013, respectively.
	-3	Net of tax benefit of $4.8 million and $4.9 million as of Mar. 31, 2014 and Dec. 31, 2013, respectively.
Tampa Electric Company [Member]	'
Other Comprehensive Income	'
	Other Comprehensive Income		Three months ended Mar. 31,
	(millions)		Gross			Tax			Net
	2014
	Unrealized gain on cash flow hedges		$	0		$	0		$	0
	Reclassification from AOCI to net income			0.4			(0.2	)		0.2
	Gain on cash flow hedges			0.4			(0.2	)		0.2
	Total other comprehensive income (loss)		$	0.4		($	0.2	)	$	0.2
	2013
	Unrealized gain on cash flow hedges		$	0		$	0		$	0
	Reclassification from AOCI to net income			0.4			(0.2	)		0.2
	Gain on cash flow hedges			0.4			(0.2	)		0.2
	Total other comprehensive income (loss)		$	0.4		($	0.2	)	$	0.2
Accumulated Other Comprehensive Loss	'
	Other Comprehensive Income		Three months ended Mar. 31,
	(millions)		Gross			Tax			Net
	2014
	Unrealized gain on cash flow hedges		$	0		$	0		$	0
	Reclassification from AOCI to net income			0.4			(0.2	)		0.2
	Gain on cash flow hedges			0.4			(0.2	)		0.2
	Total other comprehensive income (loss)		$	0.4		($	0.2	)	$	0.2
	2013
	Unrealized gain on cash flow hedges		$	0		$	0		$	0
	Reclassification from AOCI to net income			0.4			(0.2	)		0.2
	Gain on cash flow hedges			0.4			(0.2	)		0.2
	Total other comprehensive income (loss)		$	0.4		($	0.2	)	$	0.2
	Accumulated Other Comprehensive Loss
	(millions)		Mar. 31, 2014						Dec. 31, 2013
	Net unrealized losses from cash flow hedges (1)		($	7.6	)				($	7.8	)
	Total accumulated other comprehensive loss		($	7.6	)				($	7.8	)
	-1	Net of tax benefit of $4.7 million and $4.9 million as of Mar. 31, 2014 and Dec. 31, 2013, respectively.

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Schedule of Earnings Per Share	'
	For the three months ended Mar. 31,
	(millions, except per share amounts)	2014			2013
	Basic earnings per share
	Net income from continuing operations	$	47		$	41.2
	Amount allocated to nonvested participating shareholders		(0.2	)		(0.1	)
	Income before discontinued operations available to common shareholders - Basic	$	46.8		$	41.1
	Income from discontinued operations, net	$	3.1		$	0.3
	Amount allocated to nonvested participating shareholders		0			0
	Income from discontinued operations available to common shareholders - Basic	$	3.1		$	0.3
	Net income	$	50.1		$	41.5
	Amount allocated to nonvested participating shareholders		(0.2	)		(0.1	)
	Net income available to common shareholders - Basic	$	49.9		$	41.4
	Average common shares outstanding - Basic		215.2			214.6
	Earnings per share from continuing operations available to common shareholders - Basic	$	0.22		$	0.19
	Earnings per share from discontinued operations available to common shareholders - Basic	$	0.01		$	0
	Earnings per share available to common shareholders - Basic	$	0.23		$	0.19
	Diluted earnings per share
	Net income from continuing operations	$	47		$	41.2
	Amount allocated to nonvested participating shareholders		(0.2	)		(0.1	)
	Income before discontinued operations available to common shareholders - Diluted	$	46.8		$	41.1
	Income from discontinued operations, net	$	3.1		$	0.3
	Amount allocated to nonvested participating shareholders		0			0
	Income from discontinued operations available to common shareholders - Diluted	$	3.1		$	0.3
	Net income	$	50.1		$	41.5
	Amount allocated to nonvested participating shareholders		(0.2	)		(0.1	)
	Net income available to common shareholders - Diluted	$	49.9		$	41.4
	Unadjusted average common shares outstanding - Diluted		215.2			214.6
	Assumed conversion of stock options, unvested restricted stock and contingent performance shares, net		0.5			1
	Average common shares outstanding - Diluted		215.7			215.6
	Earnings per share from continuing operations available to common shareholders - Diluted	$	0.22		$	0.19
	Earnings per share from discontinued operations available to common shareholders - Diluted	$	0.01		$	0
	Earnings per share available to common shareholders - Diluted	$	0.23		$	0.19
	Anti-dilutive shares		0			0

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2014
Letters of Credit and Guarantees	'
	A summary of the face amount or maximum theoretical obligation under TECO Energy’s letters of credit and guarantees as of March 31, 2014 is as follows:
	Guarantees - TECO Energy
	(millions)						After(1)		Total		Liabilities Recognized
	Guarantees for the Benefit of:		2014		2015-2018		2018				at Mar. 31, 2014
	TECO Coal
	Fuel purchase related (2)		$	0.8	$	0.7	$	4	$	5.5	$	2.3
	Other subsidiaries
	Fuel purchase/energy management (2)			10		0		92.9		102.9		0.1
	Total		$	10.8	$	0.7	$	96.9	$	108.4	$	2.4
	Letters of Credit - Tampa Electric Company
	(millions)		2014		2015-2018		After(1)		Total		Liabilities Recognized
	Letters of Credit for the Benefit of:						2018				at Mar. 31, 2014
	Tampa Electric Company(2)		$	0	$	0	$	0.7	$	0.7	$	0.1
	Total		$	0	$	0	$	0.7	$	0.7	$	0.1
	-1	These letters of credit and guarantees renew annually and are shown on the basis that they will continue to renew beyond 2018.
	-2	The amounts shown are the maximum theoretical amounts guaranteed under current agreements. Liabilities recognized represent the associated obligation of TECO Energy under these agreements at March 31, 2014. The obligations under these letters of credit and guarantees include net accounts payable and net derivative liabilities.
Tampa Electric Company [Member]	'
Letters of Credit and Guarantees	'
	A summary of the face amount or maximum theoretical obligation under TEC’s letters of credit as of March 31, 2014 is as follows:
	Letters of Credit - Tampa Electric Company
	(millions)						After (1)				Liabilities Recognized
	Letters of Credit for the Benefit of:		2014		2015-2018		2018		Total		at Mar. 31, 2014
	Tampa Electric Company (2)		$	0	$	0	$	0.7	$	0.7	$	0.1
	-1	These letters of credit renew annually and are shown on the basis that they will continue to renew beyond 2018.
	-2	The amounts shown are the maximum theoretical amounts guaranteed under current agreements. Liabilities recognized represent the associated obligation of TEC under these agreements at Mar. 31, 2014. The obligations under these letters of credit include net accounts payable and net derivative liabilities.

Segment_Information_Tables

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2014
Schedule of Segment Information	'
	The management of TECO Energy reports segments based on each subsidiary’s contribution of revenues, net income and total assets as required by the accounting guidance for disclosures about segments of an enterprise and related information. All significant intercompany transactions are eliminated in the Consolidated Condensed Financial Statements of TECO Energy, but are included in determining reportable segments.
	Segment Information (1)
	(millions)		Tampa		Peoples		TECO			Other &			TECO
	Three months ended Mar. 31,		Electric		Gas		Coal			Eliminations			Energy
	2014
	Revenues - external		$	452.9	$	122.4	$	106.1		$	2.7		$	684.1
	Sales to affiliates			0.3		0.2		0			(0.5	)		0
	Total revenues			453.2		122.6		106.1			2.2			684.1
	Depreciation and amortization			62.1		13.3		9			0.5			84.9
	Total interest charges(1)			22		3.4		1.5			14.2			41.1
	Internally allocated interest (1)			0		0		1.5			(1.5	)		0
	Provision (benefit) for income taxes			26.6		9.2		(2.2	)		(6.9	)		26.7
	Net income (loss) from continuing operations			45.2		14.6		(1.6	)		(11.2	)		47
	Income from discontinued operations, net			0		0		0			3.1			3.1
	Net income (loss)		$	45.2	$	14.6	($	1.6	)	($	8.1	)	$	50.1
	2013
	Revenues - external		$	417.8	$	121.9	$	117.9		$	3.5		$	661.1
	Sales to affiliates			0.2		0		0			(0.2	)		0
	Total revenues			418		121.9		117.9			3.3			661.1
	Depreciation and amortization			59		13		9.7			0.3			82
	Total interest charges(1)			23.4		3.4		1.7			13.9			42.4
	Internally allocated interest (1)			0		0		1.6			(1.6	)		0
	Provision (benefit) for income taxes			19.8		8.7		(0.1	)		(5.2	)		23.2
	Net income (loss) from continuing operations			31.8		13.8		3			(7.4	)		41.2
	Income from discontinued operations, net			0		0		0			0.3			0.3
	Net income (loss)		$	31.8	$	13.8	$	3		($	7.1	)	$	41.5
	At Mar. 31, 2014
	Total assets		$	6,120.80	$	1,031.10	$	319.5		($	40.7	)	$	7,430.70
	At Dec. 31, 2013
	Total assets		$	6,126.90	$	1,021.20	$	316.3		($	16.4	)	$	7,448.00
	-1	Segment net income is reported on a basis that includes internally allocated financing costs. Total interest charges include internally allocated interest costs that for January 2013 through March 2014 were at a pretax rate of 6.00% based on an average of each subsidiary’s equity and indebtedness to TECO Energy assuming a 50/50 debt/equity capital structure.
Tampa Electric Company [Member]	'
Schedule of Segment Information	'
	(millions)		Tampa		Peoples		Other &			Tampa Electric
	Three months ended Mar. 31,		Electric		Gas		Eliminations			Company
	2014
	Revenues - external		$	453.1	$	122.4	$	0		$	575.5
	Sales to affiliates			0.1		0.2		(0.3	)		0
	Total revenues			453.2		122.6		(0.3	)		575.5
	Depreciation and amortization			62.1		13.3		0			75.4
	Total interest charges			22		3.4		0			25.4
	Provision for income taxes			26.6		9.2		0			35.8
	Net income		$	45.2	$	14.6	$	0		$	59.8
	2013
	Revenues - external		$	417.9	$	121.9	$	0		$	539.8
	Sales to affiliates			0.1		0		(0.1	)		0
	Total revenues			418		121.9		(0.1	)		539.8
	Depreciation and amortization			59		13		0			72
	Total interest charges			23.4		3.4		0			26.8
	Provision for income taxes			19.8		8.7		0			28.5
	Net income		$	31.8	$	13.8	$	0		$	45.6
	Total assets at Mar. 31, 2014		$	5,871.00	$	999.4	($	5.1	)	$	6,865.30
	Total assets at Dec. 31, 2013		$	5,895.40	$	989.3	($	8.9	)	$	6,875.80

Accounting_for_Derivative_Inst1

Accounting for Derivative Instruments and Hedging Activities (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Values and Locations of Derivative Instruments Recorded on Balance Sheet	'
	The following table presents the derivatives that are designated as cash flow hedges at March 31, 2014 and Dec. 31, 2013:
	Total Derivatives(1)
			Mar. 31,				Dec. 31,
	(millions)		2014				2013
	Current assets		$	15.6			$	9.7
	Long-term assets			0.2				0.3
	Total assets		$	15.8			$	10
	Current liabilities		$	0.1			$	0.1
	Long-term liabilities			0.1				0.2
	Total liabilities		$	0.2			$	0.3
	-1	Amounts presented above are on a gross basis, with asset and liability positions netted by counterparty in accordance with accounting standards for derivatives and hedging.
Gross Amounts of Derivatives and Their Related Offset Amounts	'
	The following table presents the gross amounts of derivatives and their related offset amounts as permitted by their respective master netting agreements at March 31, 2014 and Dec. 31, 2013.
	Offsetting of Derivative Assets and Liabilities
	(millions)
			Gross Amounts				Gross				Net Amounts of
			of Recognized				Amounts offset				Assets (Liabilities)
			Assets				on the Balance				Presented on the
			(Liabilities)				Sheet				Balance Sheet
	Mar. 31, 2014
	Description
	Derivative assets		$	16.1			$	(0.3	)		$	15.8
	Derivative liabilities		$	(0.5	)		$	0.3			$	(0.2	)
	Dec. 31, 2013
	Description
	Derivative assets		$	10.5			$	(0.5	)		$	10
	Derivative liabilities		$	(0.8	)		$	0.5			$	(0.3	)
Effect of Hedging Instruments on OCI and Income	'
	The following table presents the effect of hedging instruments on OCI and income for the three months ended March 31:
			Amount of				Location of Gain/(Loss)		Amount of
			Gain/(Loss) on				Reclassified From AOCI		Gain/(Loss)
			Derivatives				Into Income		Reclassified
			Recognized in						From AOCI
	(millions)		OCI						Into Income
	Derivatives in Cash Flow Hedging Relationships			Effective						Effective
				Portion(1)						Portion(1)
	2014
	Interest rate contracts		$	0			Interest expense		($	0.2	)
	Commodity contracts:
	Diesel fuel derivatives			(0.1	)		Mining related costs			(0.1	)
	Total		($	0.1	)				($	0.3	)
	2013
	Interest rate contracts		$	0			Interest expense		($	0.2	)
	Commodity contracts:
	Diesel fuel derivatives			0.2			Mining related costs			0
	Total		$	0.2					($	0.2	)
	-1	Changes in OCI and AOCI are reported in after-tax dollars.
	The following table presents the derivative activity for instruments classified as qualifying cash flow hedges for the three months ended March 31:
			Fair Value				Amount of				Amount of
			Asset/				Gain/(Loss)				Gain/(Loss)
			(Liability)				Recognized				Reclassified From
	(millions)						in OCI (1)				AOCI Into Income
	2014
	Interest rate swaps		$	0			$	0			($	0.2	)
	Diesel fuel derivatives			0				(0.1	)			(0.1	)
	Total		$	0			($	0.1	)		($	0.3	)
	2013
	Interest rate swaps		$	0			$	0			($	0.2	)
	Diesel fuel derivatives			(0.6	)			0.2				0
	Total		($	0.6	)		$	0.2			($	0.2	)
	-1	Changes in OCI and AOCI are reported in after-tax dollars.
Derivative Volumes Expected to Settle	'
	The following table presents by commodity type the company’s derivative volumes that, as of March 31, 2014, are expected to settle during the 2014, 2015 and 2016 fiscal years:
			Diesel Fuel Contracts								Natural Gas Contracts
	(millions)		(Gallons)								(MMBTUs)
	Year		Physical				Financial				Physical				Financial
	2014			0				1.5				0				26.9
	2015			0				0				0				18.5
	2016			0				0				0				1.7
	Total			0				1.5				0				47.1
Fair Value of Overall Contractual Contingent Liability Positions	'
	The table below presents the fair value of the overall contractual contingent liability positions for the company’s derivative activity at March 31, 2014:
	Contingent Features
	(millions)		Fair				Derivative				Posted
	At Mar. 31, 2014		Value				Exposure				Collateral
			Asset/				Asset/
			(Liability)				(Liability)
	Credit Rating		($	0.1	)		($	0.1	)		$	0
Derivatives Designated as Hedging Instruments [Member]	'
Fair Values and Locations of Derivative Instruments Recorded on Balance Sheet	'
	The following tables present the fair values and locations of derivative instruments recorded on the balance sheet at March 31, 2014 and Dec. 31, 2013:
	Derivatives Designated as Hedging Instruments
			Asset Derivatives								Liability Derivatives
	(millions)		Balance Sheet				Fair				Balance Sheet		Fair
	Mar. 31, 2014		Location				Value				Location		Value
	Commodity Contracts:
	Diesel fuel derivatives:
	Current			Derivative assets			$	0.1			Derivative liabilities		$	0.1
	Long-term			Derivative assets				0			Derivative liabilities			0
	Natural gas derivatives:
	Current			Derivative assets				15.5			Derivative liabilities			0
	Long-term			Derivative assets				0.2			Derivative liabilities			0.1
	Total derivatives designated as hedging instruments						$	15.8					$	0.2
			Asset Derivatives								Liability Derivatives
	(millions)		Balance Sheet				Fair				Balance Sheet				Fair
	Dec. 31, 2013		Location				Value				Location				Value
	Commodity Contracts:
	Diesel fuel derivatives:
	Current			Derivative assets			$	0.2				Derivative liabilities			$	0.1
	Long-term			Derivative assets				0				Derivative liabilities				0
	Natural gas derivatives:
	Current			Derivative assets				9.5				Derivative liabilities				0
	Long-term			Derivative assets				0.3				Derivative liabilities				0.2
	Total derivatives designated as hedging instruments						$	10							$	0.3
Natural Gas Derivatives [Member]	'
Fair Values and Locations of Derivative Instruments Recorded on Balance Sheet	'
	The following table presents the derivative hedges of natural gas contracts at March 31, 2014 and Dec. 31, 2013 to limit the exposure to changes in market price for natural gas used to produce energy and natural gas purchased for resale to customers:
	Natural Gas Derivatives
	(millions)		Mar. 31,				Dec. 31,
			2014				2013
	Current assets		$	15.5			$	9.5
	Long-term assets			0.2				0.3
	Total assets		$	15.7			$	9.8
	Current liabilities		$	0			$	0
	Long-term liabilities			0.1				0.2
	Total liabilities		$	0.1			$	0.2
Diesel Fuel Derivatives [Member]	'
Fair Values and Locations of Derivative Instruments Recorded on Balance Sheet	'
	The following table presents the derivative hedges of diesel fuel contracts at March 31, 2014 and Dec. 31, 2013 to limit the exposure to changes in the market price for diesel fuel used in the production of coal:
	Diesel Fuel Derivatives
			Mar. 31,				Dec. 31,
	(millions)		2014				2013
	Current assets		$	0.1			$	0.2
	Long-term assets			0				0
	Total assets		$	0.1			$	0.2
	Current liabilities		$	0.1			$	0.1
	Long-term liabilities			0				0
	Total liabilities		$	0.1			$	0.1
Energy Related Derivatives [Member]	'
Fair Values and Locations of Derivative Instruments Recorded on Balance Sheet	'
	The following tables present the effect of energy related derivatives on the fuel recovery clause mechanism in the Consolidated Condensed Balance Sheets as of March 31, 2014 and Dec. 31, 2013:
	Energy Related Derivatives
			Asset Derivatives						Liability Derivatives
	(millions)		Balance Sheet		Fair				Balance Sheet		Fair
	Mar. 31, 2014		Location (1)		Value				Location (1)		Value
	Commodity Contracts:
	Natural gas derivatives:
	Current		Regulatory liabilities		$	15.5			Regulatory assets		$	0
	Long-term		Regulatory liabilities			0.2			Regulatory assets			0.1
	Total				$	15.7					$	0.1
	(millions)		Balance Sheet		Fair				Balance Sheet		Fair
	Dec. 31, 2013		Location (1)		Value				Location (1)		Value
	Commodity Contracts:
	Natural gas derivatives:
	Current		Regulatory liabilities		$	9.5			Regulatory assets		$	0
	Long-term		Regulatory liabilities			0.3			Regulatory assets			0.2
	Total				$	9.8					$	0.2
	-1	Natural gas derivatives are deferred in accordance with accounting standards for regulated operations and all increases and decreases in the cost of natural gas supply are passed on to customers with the fuel recovery clause mechanism. As gains and losses are realized in future periods, they will be recorded as fuel costs in the Consolidated Condensed Statements of Income.
Tampa Electric Company [Member]	'
Gross Amounts of Derivatives and Their Related Offset Amounts	'
	The following table presents the gross amounts of derivatives and their related offset amounts as permitted by their respective master netting agreements at March 31, 2014 and Dec. 31, 2013. There was no collateral posted with or received from any counterparties:
	Offsetting of Derivative Assets and Liabilities
			Gross Amounts				Gross Amounts				Net Amounts of
			of Recognized				offset on the				Assets (Liabilities)
			Assets				Balance Sheet				Presented on the
	(millions)		(Liabilities)								Balance Sheet
	Mar. 31, 2014
	Description
	Derivative assets		$	16			$	(0.3	)		$	15.7
	Derivative liabilities		$	(0.4	)		$	0.3			$	(0.1	)
	Dec. 31, 2013
	Description
	Derivative assets		$	10.3			$	(0.5	)		$	9.8
	Derivative liabilities		$	(0.7	)		$	0.5			$	(0.2	)
Effect of Hedging Instruments on OCI and Income	'
	The following table presents the effect of hedging instruments on OCI and income for the three months ended March 31:
	(millions)		Amount of				Location of Gain/(Loss)		Amount of
			Gain/(Loss) on				Reclassified From AOCI		Gain/(Loss)
			Derivatives				Into Income		Reclassified
			Recognized in						From AOCI
			OCI						Into Income
	Derivatives in Cash Flow Hedging Relationships			Effective						Effective
										Portion	(1)
				Portion	(1)
	2014
	Interest rate contracts		$	0			Interest expense		($	0.2	)
	Total		$	0					($	0.2	)
	2013
	Interest rate contracts		$	0			Interest expense		($	0.2	)
	Total		$	0					($	0.2	)
	-1	Changes in OCI and AOCI are reported in after-tax dollars.
Derivative Volumes Expected to Settle	'
	The following table presents by commodity type TEC’s derivative volumes that, as of March 31, 2014, are expected to settle during the 2014, 2015 and 2016 fiscal years:
			Natural Gas Contracts
	(millions)		(MMBTUs)
	Year		Physical				Financial
	2014			0				26.9
	2015			0				18.5
	2016			0				1.7
	Total			0				47.1
Tampa Electric Company [Member] | Natural Gas Derivatives [Member]	'
Fair Values and Locations of Derivative Instruments Recorded on Balance Sheet	'
	The following table presents the derivative hedges of natural gas contracts at March 31, 2014 and Dec. 31, 2013 to limit the exposure to changes in the market price for natural gas used to produce energy and natural gas purchased for resale to customers:
	Natural Gas Derivatives
			Mar. 31,				Dec. 31,
	(millions)		2014				2013
	Current assets		$	15.5			$	9.5
	Long-term assets			0.2				0.3
	Total assets		$	15.7			$	9.8
	Current liabilities (1)		$	0			$	0
	Long-term liabilities			0.1				0.2
	Total liabilities		$	0.1			$	0.2
	-1	Amounts presented above are on a gross basis, with asset and liability positions netted by counterparty in accordance with accounting standards for derivatives and hedging.
Tampa Electric Company [Member] | Energy Related Derivatives [Member]	'
Fair Values and Locations of Derivative Instruments Recorded on Balance Sheet	'
	The following table presents the effect of energy related derivatives on the fuel recovery clause mechanism in the Consolidated Condensed Balance Sheets as of March 31, 2014 and Dec. 31, 2013:
	Energy Related Derivatives
			Asset Derivatives						Liability Derivatives
	(millions)		Balance Sheet		Fair				Balance Sheet		Fair
	Mar. 31, 2014		Location (1)		Value				Location (1)		Value
	Commodity Contracts:
	Natural gas derivatives:
	Current		Regulatory liabilities		$	15.5			Regulatory assets		$	0
	Long-term		Regulatory liabilities			0.2			Regulatory assets			0.1
	Total				$	15.7					$	0.1
	(millions)		Balance Sheet		Fair				Balance Sheet		Fair
	Dec. 31, 2013		Location (1)		Value				Location (1)		Value
	Commodity Contracts:
	Natural gas derivatives:
	Current		Regulatory liabilities		$	9.5			Regulatory assets		$	0
	Long-term		Regulatory liabilities			0.3			Regulatory assets			0.2
	Total				$	9.8					$	0.2
	-1	Natural gas derivatives are deferred in accordance with accounting standards for regulated operations and all increases and decreases in the cost of natural gas supply are passed on to customers with the fuel recovery clause mechanism. As gains and losses are realized in future periods, they will be recorded as fuel costs in the Consolidated Condensed Statements of Income.

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2014
Schedule of Recurring Fair Value Measurements	'
	For natural gas and diesel fuel swaps, the market approach was used in determining fair value.
	Recurring Fair Value Measures
		At fair value as of Mar. 31, 2014
	(millions)	Level 1		Level 2		Level 3		Total
	Assets
	Natural gas swaps	$	0	$	15.7	$	0	$	15.7
	Diesel fuel swaps		0		0.1		0		0.1
	Total	$	0	$	15.8	$	0	$	15.8
	Liabilities
	Natural gas swaps	$	0	$	0.1	$	0	$	0.1
	Diesel fuel swaps		0		0.1		0		0.1
	Total	$	0	$	0.2	$	0	$	0.2
		At fair value as of Dec. 31, 2013
	(millions)	Level 1		Level 2		Level 3		Total
	Assets
	Natural gas swaps	$	0	$	9.8	$	0	$	9.8
	Diesel fuel swaps		0		0.2		0		0.2
	Total	$	0	$	10	$	0	$	10
	Liabilities
	Natural gas swaps	$	0	$	0.2	$	0	$	0.2
	Diesel fuel swaps		0		0.1		0		0.1
	Total	$	0	$	0.3	$	0	$	0.3
Tampa Electric Company [Member]	'
Schedule of Recurring Fair Value Measurements	'
	For all assets and liabilities presented below, the market approach was used in determining fair value.
	Recurring Derivative Fair Value Measures
		At fair value as of Mar. 31, 2014
	(millions)	Level 1		Level 2		Level 3		Total
	Assets
	Natural gas swaps	$	0	$	15.7	$	0	$	15.7
	Total	$	0	$	15.7	$	0	$	15.7
	Liabilities
	Natural gas swaps	$	0	$	0.1	$	0	$	0.1
	Total	$	0	$	0.1	$	0	$	0.1
		At fair value as of Dec. 31, 2013
	(millions)	Level 1		Level 2		Level 3		Total
	Assets
	Natural gas swaps	$	0	$	9.8	$	0	$	9.8
	Total	$	0	$	9.8	$	0	$	9.8
	Liabilities
	Natural gas swaps	$	0	$	0.2	$	0	$	0.2
	Total	$	0	$	0.2	$	0	$	0.2

Discontinued_Operations_Tables

Discontinued Operations (Tables) (TECO Guatemala [Member])	3 Months Ended
	Mar. 31, 2014
TECO Guatemala [Member]	'
Components of Discontinued Operations	'
	The following table provides selected components of discontinued operations:
	Components of income from discontinued operations
	(millions)
	Three months ended Mar. 31,	2014		2013
	Revenues	$	0	$	0
	Income from operations		5		0.4
	Income from discontinued operations		5		0.4
	Provision for income taxes		1.9		0.1
	Income from discontinued operations, net	$	3.1	$	0.3

Summary_of_Significant_Account2

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Dec. 31, 2013
			Tampa Electric Company [Member]	Tampa Electric Company [Member]	Unbilled Revenues [Member]	Unbilled Revenues [Member]	Unbilled Revenues [Member]	Unbilled Revenues [Member]
							Tampa Electric Company [Member]	Tampa Electric Company [Member]
Summary Of Significant Accounting Policies [Line Items]	'	'	'	'	'	'	'	'
Unbilled revenues	'	'	'	'	$48.10	$46.70	$48.10	$46.70
Franchise fees and gross receipts taxes	$27.20	$25.40	$27.20	$25.40	'	'	'	'

Regulatory_Additional_Informat

Regulatory - Additional Information (Detail) (Tampa Electric Company [Member], USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Annual accrual storm damage reserve	8	'
Storm damage reserve	56.1	56.1
Transmission and Delivery Storm Reserve [Member]	'	'
Storm damage cost recovery period	'12 months	'12 months

Regulatory_Schedule_of_Regulat

Regulatory - Schedule of Regulatory Assets and Regulatory Liabilities (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Regulatory assets:	'	'
Regulatory assets	$321.50	$327.40
Less: Current portion	32.7	34.3
Long-term regulatory assets	288.8	293.1
Regulatory liabilities:	'	'
Regulatory liabilities	715.1	717.2
Less: Current portion	90.1	85.8
Long-term regulatory liabilities	625	631.4
Regulatory Tax Liability [Member]	'	'
Regulatory liabilities:	'	'
Regulatory liabilities	5.8	9.8
Cost-Recovery Clauses [Member]	'	'
Regulatory liabilities:	'	'
Regulatory liabilities	58.9	54.5
Transmission and Delivery Storm Reserve [Member]	'	'
Regulatory liabilities:	'	'
Regulatory liabilities	56.1	56.1
Deferred Gain on Property Sales [Member]	'	'
Regulatory liabilities:	'	'
Regulatory liabilities	1.7	2
Provision for Stipulation and Other [Member]	'	'
Regulatory liabilities:	'	'
Regulatory liabilities	0.8	0.8
Accumulated Reserve-Cost of Removal [Member]	'	'
Regulatory liabilities:	'	'
Regulatory liabilities	591.8	594
Total Other Regulatory Liabilities [Member]	'	'
Regulatory liabilities:	'	'
Regulatory liabilities	709.3	707.4
Regulatory Tax Asset [Member]	'	'
Regulatory assets:	'	'
Regulatory assets	67.9	67.4
Cost-Recovery Clauses [Member]	'	'
Regulatory assets:	'	'
Regulatory assets	3.3	6.1
Postretirement Benefit Costs [Member]	'	'
Regulatory assets:	'	'
Regulatory assets	180.2	182.7
Deferred Bond Refinancing Costs [Member]	'	'
Regulatory assets:	'	'
Regulatory assets	7.8	8
Environmental Remediation [Member]	'	'
Regulatory assets:	'	'
Regulatory assets	51.4	51.4
Competitive Rate Adjustment [Member]	'	'
Regulatory assets:	'	'
Regulatory assets	3.4	4.1
Other [Member]	'	'
Regulatory assets:	'	'
Regulatory assets	7.5	7.7
Total Other Regulatory Assets [Member]	'	'
Regulatory assets:	'	'
Regulatory assets	$253.60	$260

Regulatory_Schedule_of_Regulat1

Regulatory - Schedule of Regulatory Assets and Regulatory Liabilities (Parenthetical) (Detail)	3 Months Ended
	Mar. 31, 2014
Schedule Of Regulatory Assets And Liabilities [Line Items]	'
Amortization period	'5-year
Tampa Electric Company [Member]	'
Schedule Of Regulatory Assets And Liabilities [Line Items]	'
Amortization period	'5-year

Regulatory_Regulatory_Assets_a

Regulatory - Regulatory Assets and Related Recovery Periods (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Regulatory Assets [Line Items]	'	'
Regulatory assets	$321.50	$327.40
Tampa Electric Company [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	321.5	327.4
Clause Recoverable [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	6.7	10.2
Clause Recoverable [Member] | Tampa Electric Company [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	6.7	10.2
Regulatory Tax Asset [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	67.9	67.4
Regulatory Tax Asset [Member] | Tampa Electric Company [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	67.9	67.4
Capital Structure and Other [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	63.7	64.2
Capital Structure and Other [Member] | Tampa Electric Company [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	63.7	64.2
Components of Rate Base [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	183.2	185.6
Components of Rate Base [Member] | Tampa Electric Company [Member]	'	'
Regulatory Assets [Line Items]	'	'
Regulatory assets	$183.20	$185.60

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Income Taxes [Line Items]	'	'
Income tax examination period	'1 year	'
Effective tax rate	36.22%	35.95%
Tampa Electric Company [Member]	'	'
Income Taxes [Line Items]	'	'
Statutes of limitations	'3 years	'
Income tax examination period	'1 year	'
Minimum [Member]	'	'
Income Taxes [Line Items]	'	'
Statutes of limitations	'3 years	'
Maximum [Member]	'	'
Income Taxes [Line Items]	'	'
Statutes of limitations	'4 years	'

Employee_Postretirement_Benefi2

Employee Postretirement Benefits - Schedule of Net Periodic Benefit Cost (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Pension Benefits [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Service cost	$4.10	$4.80
Interest cost on projected benefit obligations	8.2	7.2
Expected return on assets	-10.3	-9.7
Amortization of:	'	'
Prior service cost	-0.1	-0.1
Actuarial loss	3.2	5
Net pension expense recognized in the Consolidated Condensed Statements of Income	5.1	7.2
Other Postretirement Benefits [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Service cost	0.6	0.7
Interest cost on projected benefit obligations	2.6	2.3
Expected return on assets	0	0
Amortization of:	'	'
Prior service cost	0	-0.1
Actuarial loss	0	0.3
Net pension expense recognized in the Consolidated Condensed Statements of Income	$3.20	$3.20

Employee_Postretirement_Benefi3

Employee Postretirement Benefits - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Defined Benefit Plan Disclosure [Line Items]	'	'
Long-term EROA	7.25%	'
Contributions to pension plan	$16	'
Reclassification of AOCI to net income as part of periodic benefit expense	0.6	'
Reclassification of regulatory assets to net income as part of periodic benefit expense	2.5	'
Tampa Electric Company [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Long-term EROA	7.25%	'
Contributions to pension plan	13	'
Reclassification of regulatory assets to net income as part of periodic benefit expense	2.5	'
Pension Benefits [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Discount rate	5.12%	'
Pension Benefits [Member] | Tampa Electric Company [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Discount rate	5.12%	'
Net pension expense	3.8	5.3
Other Postretirement Benefits [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Discount rate	5.10%	'
Other Postretirement Benefits [Member] | Tampa Electric Company [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Discount rate	5.10%	'
Net pension expense	$2.60	$2.60

ShortTerm_Debt_Credit_Faciliti

Short-Term Debt - Credit Facilities (Detail) (USD $)	Mar. 31, 2014	Feb. 14, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Line of Credit Facility [Line Items]	'	'	'
Credit Facilities	$675	'	$675
Borrowings Outstanding	29	'	84
Letters of Credit Outstanding	0.7	'	0.7
Tampa Electric Company [Member]	'	'	'
Line of Credit Facility [Line Items]	'	'	'
Credit Facilities	475	'	475
Borrowings Outstanding	29	'	84
Letters of Credit Outstanding	0.7	'	0.7
Tampa Electric Company [Member] | 5-year Facility [Member]	'	'	'
Line of Credit Facility [Line Items]	'	'	'
Credit Facilities	325	'	325
Borrowings Outstanding	0	'	6
Letters of Credit Outstanding	0.7	'	0.7
Tampa Electric Company [Member] | 1-year Accounts Receivable Facility [Member]	'	'	'
Line of Credit Facility [Line Items]	'	'	'
Credit Facilities	150	150	150
Borrowings Outstanding	29	'	78
Letters of Credit Outstanding	0	'	0
TECO Energy [Member] | 5-year Facility [Member]	'	'	'
Line of Credit Facility [Line Items]	'	'	'
Credit Facilities	200	'	200
Borrowings Outstanding	0	'	0
Letters of Credit Outstanding	$0	'	$0

ShortTerm_Debt_Credit_Faciliti1

Short-Term Debt - Credit Facilities (Parenthetical) (Detail)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Line of Credit Facility [Line Items]	'	'
Credit facility maturity date	17-Dec-18	17-Dec-18
Tampa Electric Company [Member]	'	'
Line of Credit Facility [Line Items]	'	'
Credit facility maturity date	17-Dec-18	17-Dec-18

ShortTerm_Debt_Additional_Info

Short-Term Debt - Additional Information (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Feb. 14, 2014	Dec. 31, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013
In Millions, unless otherwise specified			Tampa Electric Company [Member]	Tampa Electric Company [Member]	Tampa Electric Company [Member]	Tampa Electric Company [Member]	Tampa Electric Company [Member]	Tampa Electric Company [Member]	Tampa Electric Company [Member]	Tampa Electric Company [Member]	Tampa Electric Company [Member]
					1-year Accounts Receivable Facility [Member]	1-year Accounts Receivable Facility [Member]	1-year Accounts Receivable Facility [Member]	Minimum [Member]	Minimum [Member]	Maximum [Member]	Maximum [Member]
Line of Credit Facility [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Commitment fees, percentage	'	'	0.70%	'	0.70%	'	'	0.13%	0.13%	0.30%	0.30%
Weighted-average interest rate	'	'	0.63%	0.56%	'	'	'	'	'	'	'
Amended credit facility	$675	$675	$475	$475	$150	$150	$150	'	'	'	'
Debt instrument maturity date	'	'	'Feb. 13, 2015	'	'	'	'	'	'	'	'
Basis spread on federal funds rate	'	'	0.50%	'	0.50%	'	'	'	'	'	'

LongTerm_Debt_Additional_Infor

Long-Term Debt - Additional Information (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Debt Instrument [Line Items]	'	'
Long-term debt, carrying amount	$2,921.10	$2,921.10
Estimated fair value	3,209.70	3,184.10
Tampa Electric Company [Member]	'	'
Debt Instrument [Line Items]	'	'
Long-term debt, carrying amount	1,880.80	1,880.80
Estimated fair value	$2,058.40	$2,042

Other_Comprehensive_Income_Oth

Other Comprehensive Income - Other Comprehensive Income (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Other Comprehensive Income Loss [Line Items]	'	'
Unrealized gain on cash flow hedges, Gross	($0.10)	$0.30
Reclassification from AOCI to net income, Gross	0.4	0.3
Gain on cash flow hedges, Gross	0.3	0.6
Amortization of unrecognized benefit costs, Gross	0.8	1.1
Increase in unrecognized post employment costs, Gross	-12.9	'
Total other comprehensive income (loss), Gross	-11.8	1.7
Unrealized gain on cash flow hedges, Tax	0	-0.1
Reclassification from AOCI to net income, Tax	-0.1	-0.1
Gain on cash flow hedges, Tax	-0.1	-0.2
Amortization of unrecognized benefit costs, Tax	-0.3	-0.4
Increase in unrecognized post employment costs, Tax	4.7	'
Total other comprehensive income (loss), Tax	4.3	-0.6
Unrealized gain (loss) on cash flow hedges, Net	-0.1	0.2
Reclassification from AOCI to net income, Net	0.3	0.2
Gain on cash flow hedges, Net	0.2	0.4
Amortization of unrecognized benefit costs, Net	0.5	0.7
Increase in unrecognized post employment costs, Net	-8.2	0
Other comprehensive income, net of tax	-7.5	1.1
Tampa Electric Company [Member]	'	'
Other Comprehensive Income Loss [Line Items]	'	'
Unrealized gain on cash flow hedges, Gross	0	0
Reclassification from AOCI to net income, Gross	0.4	0.4
Gain on cash flow hedges, Gross	0.4	0.4
Total other comprehensive income (loss), Gross	0.4	0.4
Unrealized gain on cash flow hedges, Tax	0	0
Reclassification from AOCI to net income, Tax	-0.2	-0.2
Gain on cash flow hedges, Tax	-0.2	-0.2
Total other comprehensive income (loss), Tax	-0.2	-0.2
Unrealized gain (loss) on cash flow hedges, Net	0	0
Reclassification from AOCI to net income, Net	0.2	0.2
Gain on cash flow hedges, Net	0.2	0.2
Other comprehensive income, net of tax	$0.20	$0.20

Other_Comprehensive_Income_Acc

Other Comprehensive Income - Accumulated Other Comprehensive Loss (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Net unrealized losses from cash flow hedges	($7.60)	($7.80)
Total accumulated other comprehensive loss	-20.7	-13.2
Tampa Electric Company [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Net unrealized losses from cash flow hedges	-7.6	-7.8
Total accumulated other comprehensive loss	-7.6	-7.8
Pension Benefits [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Unrecognized other benefit loss, prior service cost and transition obligation	-20	-20.5
Other Postretirement Benefits [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Unrecognized other benefit loss, prior service cost and transition obligation	$6.90	$15.10

Other_Comprehensive_Income_Acc1

Other Comprehensive Income - Accumulated Other Comprehensive Loss (Parenthetical) (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Net unrealized losses from cash flow hedges, tax benefit	$4.80	$4.90
Pension Benefits [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Unrecognized pension and other benefit loss, prior service cost (credit) and transition obligation, tax expense (benefit)	12.3	12.6
Other Postretirement Benefits [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Unrecognized pension and other benefit loss, prior service cost (credit) and transition obligation, tax expense (benefit)	4.4	9.1
Tampa Electric Company [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Net unrealized losses from cash flow hedges, tax benefit	$4.70	$4.90

Earnings_Per_Share_Schedule_of

Earnings Per Share - Schedule of Earnings Per Share (Detail) (USD $)	3 Months Ended
In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Basic earnings per share	'	'
Net income from continuing operations	$47	$41.20
Amount allocated to nonvested participating shareholders	-0.2	-0.1
Income before discontinued operations available to common shareholders-Basic	46.8	41.1
Income from discontinued operations, net	3.1	0.3
Amount allocated to nonvested participating shareholders	0	0
Income from discontinued operations available to common shareholders-Basic	3.1	0.3
Net income	50.1	41.5
Amount allocated to nonvested participating shareholders	-0.2	-0.1
Net income available to common shareholders-Basic	49.9	41.4
Average common shares outstanding-Basic	215.2	214.6
Earnings per share from continuing operations available to common shareholders-Basic	$0.22	$0.19
Earnings per share from discontinued operations available to common shareholders-Basic	$0.01	$0
Earnings per share attributable to TECO Energy - Basic	$0.23	$0.19
Diluted earnings per share	'	'
Net income from continuing operations	47	41.2
Amount allocated to nonvested participating shareholders	-0.2	-0.1
Income before discontinued operations available to common shareholders-Diluted	46.8	41.1
Income from discontinued operations, net	3.1	0.3
Amount allocated to nonvested participating shareholders	0	0
Income from discontinued operations available to common shareholders-Diluted	3.1	0.3
Net income	50.1	41.5
Amount allocated to nonvested participating shareholders	-0.2	-0.1
Net income available to common shareholders-Diluted	$49.90	$41.40
Unadjusted average common shares outstanding-Diluted	215.2	214.6
Assumed conversion of stock options, unvested restricted stock and contingent performance shares, net	0.5	1
Average common shares outstanding-Diluted	215.7	215.6
Earnings per share from continuing operations available to common shareholders-Diluted	$0.22	$0.19
Earnings per share from discontinued operations available to common shareholders-Diluted	$0.01	$0
Earnings per share attributable to TECO Energy - Diluted	$0.23	$0.19
Anti-dilutive shares	0	0

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (PGS [Member], USD $)	Mar. 31, 2014
In Millions, unless otherwise specified
PGS [Member]	'
Site Contingency [Line Items]	'
Ultimate financial liability to superfund sites and former MGP sites	$38.40

Commitments_and_Contingencies_2

Commitments and Contingencies - Letters of Credit and Guarantees (Detail) (USD $)	Mar. 31, 2014
In Millions, unless otherwise specified
Guarantor Obligations [Line Items]	'
2014	$10.80
2015-2018	0.7
After 2018	96.9
Total	108.4
Liabilities Recognized at Mar. 31, 2014	2.4
Tampa Electric Company [Member]	'
Guarantor Obligations [Line Items]	'
2014	0
2015-2018	0
After 2018	0.7
Total	0.7
Liabilities Recognized at Mar. 31, 2014	0.1
Tampa Electric Company [Member] | Letters of Credit [Member]	'
Guarantor Obligations [Line Items]	'
2014	0
2015-2018	0
After 2018	0.7
Total	0.7
Liabilities Recognized at Mar. 31, 2014	0.1
TECO Coal [Member] | Fuel Purchase Related [Member]	'
Guarantor Obligations [Line Items]	'
2014	0.8
2015-2018	0.7
After 2018	4
Total	5.5
Liabilities Recognized at Mar. 31, 2014	2.3
Other Subsidiaries [Member] | Fuel Purchase / Energy Management [Member]	'
Guarantor Obligations [Line Items]	'
2014	10
2015-2018	0
After 2018	92.9
Total	102.9
Liabilities Recognized at Mar. 31, 2014	$0.10

Segment_Information_Schedule_o

Segment Information - Schedule of Segment Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Segment Reporting Information [Line Items]	'	'	'
Total revenues	$684.10	$661.10	'
Depreciation and amortization	84.9	82	'
Total interest charges	41.1	42.4	'
Internally allocated interest	0	0	'
Provision (benefit) for income taxes	26.7	23.2	'
Net income (loss) from continuing operations	47	41.2	'
Income from discontinued operations, net	3.1	0.3	'
Net income	50.1	41.5	'
Total assets	7,430.70	'	7,448
Other & Eliminations [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	2.2	3.3	'
Depreciation and amortization	0.5	0.3	'
Total interest charges	14.2	13.9	'
Internally allocated interest	-1.5	-1.6	'
Provision (benefit) for income taxes	-6.9	-5.2	'
Net income (loss) from continuing operations	-11.2	-7.4	'
Income from discontinued operations, net	3.1	0.3	'
Net income	-8.1	-7.1	'
Total assets	-40.7	'	-16.4
Revenues - External [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	684.1	661.1	'
Revenues - External [Member] | Other & Eliminations [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	2.7	3.5	'
Sales to Affiliates [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	0	0	'
Sales to Affiliates [Member] | Other & Eliminations [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	-0.5	-0.2	'
Tampa Electric [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	453.2	418	'
Depreciation and amortization	62.1	59	'
Total interest charges	22	23.4	'
Internally allocated interest	0	0	'
Provision (benefit) for income taxes	26.6	19.8	'
Net income (loss) from continuing operations	45.2	31.8	'
Income from discontinued operations, net	0	0	'
Net income	45.2	31.8	'
Total assets	6,120.80	'	6,126.90
Tampa Electric [Member] | Revenues - External [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	452.9	417.8	'
Tampa Electric [Member] | Sales to Affiliates [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	0.3	0.2	'
People Gas [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	122.6	121.9	'
Depreciation and amortization	13.3	13	'
Total interest charges	3.4	3.4	'
Internally allocated interest	0	0	'
Provision (benefit) for income taxes	9.2	8.7	'
Net income (loss) from continuing operations	14.6	13.8	'
Income from discontinued operations, net	0	0	'
Net income	14.6	13.8	'
Total assets	1,031.10	'	1,021.20
People Gas [Member] | Revenues - External [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	122.4	121.9	'
People Gas [Member] | Sales to Affiliates [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	0.2	0	'
TECO Coal [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	106.1	117.9	'
Depreciation and amortization	9	9.7	'
Total interest charges	1.5	1.7	'
Internally allocated interest	1.5	1.6	'
Provision (benefit) for income taxes	-2.2	-0.1	'
Net income (loss) from continuing operations	-1.6	3	'
Income from discontinued operations, net	0	0	'
Net income	-1.6	3	'
Total assets	319.5	'	316.3
TECO Coal [Member] | Revenues - External [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	106.1	117.9	'
TECO Coal [Member] | Sales to Affiliates [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	0	0	'
Tampa Electric Company [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	575.5	539.8	'
Depreciation and amortization	75.4	72	'
Total interest charges	25.4	26.8	'
Provision (benefit) for income taxes	35.8	28.5	'
Net income	59.8	45.6	'
Total assets	6,865.30	6,875.80	6,875.80
Tampa Electric Company [Member] | Other & Eliminations [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	-0.3	-0.1	'
Depreciation and amortization	0	0	'
Total interest charges	0	0	'
Provision (benefit) for income taxes	0	0	'
Net income	0	0	'
Total assets	-5.1	-8.9	'
Tampa Electric Company [Member] | Revenues - External [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	575.5	539.8	'
Tampa Electric Company [Member] | Revenues - External [Member] | Other & Eliminations [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	0	0	'
Tampa Electric Company [Member] | Sales to Affiliates [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	0	0	'
Tampa Electric Company [Member] | Sales to Affiliates [Member] | Other & Eliminations [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	-0.3	-0.1	'
Tampa Electric Company [Member] | Tampa Electric [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	453.2	418	'
Depreciation and amortization	62.1	59	'
Total interest charges	22	23.4	'
Provision (benefit) for income taxes	26.6	19.8	'
Net income	45.2	31.8	'
Total assets	5,871	5,895.40	'
Tampa Electric Company [Member] | Tampa Electric [Member] | Revenues - External [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	453.1	417.9	'
Tampa Electric Company [Member] | Tampa Electric [Member] | Sales to Affiliates [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	0.1	0.1	'
Tampa Electric Company [Member] | People Gas [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	122.6	121.9	'
Depreciation and amortization	13.3	13	'
Total interest charges	3.4	3.4	'
Provision (benefit) for income taxes	9.2	8.7	'
Net income	14.6	13.8	'
Total assets	999.4	989.3	'
Tampa Electric Company [Member] | People Gas [Member] | Revenues - External [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Total revenues	122.4	121.9	'
Tampa Electric Company [Member] | People Gas [Member] | Sales to Affiliates [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Sales to affiliates	$0.20	$0	'

Segment_Information_Schedule_o1

Segment Information - Schedule of Segment Information (Parenthetical) (Detail)	3 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Internally allocated interest costs, pre tax rate	6.00%
Capital structure assumption, debt to equity ratio	50.00%

Accounting_for_Derivative_Inst2

Accounting for Derivative Instruments and Hedging Activities - Derivatives Designated as Cash Flow Hedges (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Derivatives, Fair Value [Line Items]	'	'
Current assets	$15.60	$9.70
Long-term assets	0.2	0.3
Total assets	15.8	10
Current liabilities	0.1	0.1
Long-term liabilities	0.1	0.2
Total liabilities	0.2	0.3
Tampa Electric Company [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Current assets	32.7	34.3
Long-term assets	0.2	0.3
Long-term liabilities	0.1	0.2
Diesel Fuel Derivatives [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Current assets	0.1	0.2
Long-term assets	0	0
Total assets	0.1	0.2
Current liabilities	0.1	0.1
Long-term liabilities	0	0
Total liabilities	0.1	0.1
Natural Gas Derivatives [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Current assets	15.5	9.5
Long-term assets	0.2	0.3
Total assets	15.7	9.8
Current liabilities	0	0
Long-term liabilities	0.1	0.2
Total liabilities	0.1	0.2
Natural Gas Derivatives [Member] | Tampa Electric Company [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Current assets	15.5	9.5
Long-term assets	0.2	0.3
Total assets	15.7	9.8
Current liabilities	0	0
Long-term liabilities	0.1	0.2
Total liabilities	$0.10	$0.20

Accounting_for_Derivative_Inst3

Accounting for Derivative Instruments and Hedging Activities - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Derivative [Line Items]	'	'
Collateral posted with or received from any counterparties	$0	$0
Net loss related to cash flow hedges and interest rate swaps in AOCI, after tax	7.6	7.8
Net pretax losses expected to be reclassified from regulatory assets or liabilities	15.5	'
Tampa Electric Company [Member]	'	'
Derivative [Line Items]	'	'
Net loss related to cash flow hedges and interest rate swaps in AOCI, after tax	7.6	7.8
Net pretax losses expected to be reclassified from regulatory assets or liabilities	15.5	'
Interest Rate Swap [Member]	'	'
Derivative [Line Items]	'	'
Net loss related to cash flow hedges and interest rate swaps in AOCI, after tax	$7.60	$7.80
Diesel Fuel [Member]	'	'
Derivative [Line Items]	'	'
Maximum length of time hedging in future cash flow	31-Dec-14	'
Natural Gas Contracts [Member]	'	'
Derivative [Line Items]	'	'
Maximum length of time hedging in future cash flow	31-Dec-16	'

Accounting_for_Derivative_Inst4

Accounting for Derivative Instruments and Hedging Activities - Gross Amounts of Derivatives and Their Related Offset Amounts (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Derivative [Line Items]	'	'
Derivative assets, Gross Amounts of Recognized Assets	$16.10	$10.50
Derivative liabilities, Gross Amounts of Recognized (Liabilities)	-0.5	-0.8
Derivative assets, Gross Amounts offset on the Balance Sheet	-0.3	-0.5
Derivative liabilities, Gross Amounts offset on the Balance Sheet	0.3	0.5
Derivative assets, Net Amounts of Assets	15.8	10
Derivative assets, Net Amounts of Liabilities	-0.2	-0.3
Tampa Electric Company [Member]	'	'
Derivative [Line Items]	'	'
Derivative assets, Gross Amounts of Recognized Assets	16	10.3
Derivative liabilities, Gross Amounts of Recognized (Liabilities)	-0.4	-0.7
Derivative assets, Gross Amounts offset on the Balance Sheet	-0.3	-0.5
Derivative liabilities, Gross Amounts offset on the Balance Sheet	0.3	0.5
Derivative assets, Net Amounts of Assets	15.7	9.8
Derivative assets, Net Amounts of Liabilities	($0.10)	($0.20)

Accounting_for_Derivative_Inst5

Accounting for Derivative Instruments and Hedging Activities - Derivatives Designated as Hedging Instruments (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Derivatives, Fair Value [Line Items]	'	'
Current liabilities	$0.10	$0.10
Long-term derivative liabilities	0.1	0.2
Total derivatives designated as hedging instruments	0.2	0.3
Current assets	15.6	9.7
Long-term derivative assets	0.2	0.3
Total assets	15.8	10
Diesel Fuel Derivatives [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Current liabilities	0.1	0.1
Long-term derivative liabilities	0	0
Total derivatives designated as hedging instruments	0.1	0.1
Current assets	0.1	0.2
Long-term derivative assets	0	0
Total assets	0.1	0.2
Natural Gas Derivatives [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Current liabilities	0	0
Long-term derivative liabilities	0.1	0.2
Total derivatives designated as hedging instruments	0.1	0.2
Current assets	15.5	9.5
Long-term derivative assets	0.2	0.3
Total assets	15.7	9.8
Derivatives Designated as Hedging Instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Total derivatives designated as hedging instruments	0.2	0.3
Total assets	15.8	10
Derivatives Designated as Hedging Instruments [Member] | Diesel Fuel Derivatives [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Current liabilities	0.1	0.1
Long-term derivative liabilities	0	0
Current assets	0.1	0.2
Long-term derivative assets	0	0
Derivatives Designated as Hedging Instruments [Member] | Natural Gas Derivatives [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Current liabilities	0	0
Long-term derivative liabilities	0.1	0.2
Current assets	15.5	9.5
Long-term derivative assets	$0.20	$0.30

Accounting_for_Derivative_Inst6

Accounting for Derivative Instruments and Hedging Activities - Energy Related Derivatives (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified			Tampa Electric Company [Member]	Tampa Electric Company [Member]	Energy Related Derivatives [Member]	Energy Related Derivatives [Member]	Energy Related Derivatives [Member]	Energy Related Derivatives [Member]
							Tampa Electric Company [Member]	Tampa Electric Company [Member]
Derivatives, Fair Value [Line Items]	'	'	'	'	'	'	'	'
Current regulatory assets	$32.70	$34.30	$15.50	$9.50	$0	$0	$0	$0
Long-term regulatory assets	288.8	293.1	288.8	293.1	0.1	0.2	0.1	0.2
Regulatory assets	321.5	327.4	321.5	327.4	0.1	0.2	0.1	0.2
Current regulatory liabilities	90.1	85.8	90.1	85.8	15.5	9.5	15.5	9.5
Long-term regulatory liabilities	625	631.4	625	631.4	0.2	0.3	0.2	0.3
Regulatory liabilities	$715.10	$717.20	'	'	$15.70	$9.80	$15.70	$9.80

Accounting_for_Derivative_Inst7

Accounting for Derivative Instruments and Hedging Activities - Effect of Hedging Instruments on Other Comprehensive Income and Income (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Amount of Gain/(Loss) on Derivatives Recognized in OCI	($0.10)	$0.20
Amount of Gain/(Loss) on Derivatives Recognized in OCI	-0.3	-0.2
Tampa Electric Company [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Amount of Gain/(Loss) on Derivatives Recognized in OCI	0	0
Amount of Gain/(Loss) on Derivatives Recognized in OCI	-0.2	-0.2
Diesel Fuel Derivatives [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Amount of Gain/(Loss) on Derivatives Recognized in OCI	-0.1	0.2
Location of Gain/(Loss) Reclassified From AOCI Into Income	'Mining related costs	'Mining related costs
Amount of Gain/(Loss) on Derivatives Recognized in OCI	-0.1	0
Interest rate contracts [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Amount of Gain/(Loss) on Derivatives Recognized in OCI	0	0
Location of Gain/(Loss) Reclassified From AOCI Into Income	'Interest expense	'Interest expense
Amount of Gain/(Loss) on Derivatives Recognized in OCI	-0.2	-0.2
Interest rate contracts [Member] | Tampa Electric Company [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Amount of Gain/(Loss) on Derivatives Recognized in OCI	0	0
Location of Gain/(Loss) Reclassified From AOCI Into Income	'Interest expense	'Interest expense
Amount of Gain/(Loss) on Derivatives Recognized in OCI	($0.20)	($0.20)

Accounting_for_Derivative_Inst8

Accounting for Derivative Instruments and Hedging Activities - Derivative Activity for Instruments Classified as Qualifying Cash Flow Hedges (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Fair Value Asset/(Liability)	$0	($0.60)
Amount of Gain/(Loss) Recognized in OCI	-0.1	0.2
Amount of Gain/(Loss) Reclassified From AOCI Into Income	-0.3	-0.2
Diesel Fuel Derivatives [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Fair Value Asset/(Liability)	0	-0.6
Amount of Gain/(Loss) Recognized in OCI	-0.1	0.2
Amount of Gain/(Loss) Reclassified From AOCI Into Income	-0.1	0
Interest Rate Swap [Member]	'	'
Derivative Instruments, Gain (Loss) [Line Items]	'	'
Fair Value Asset/(Liability)	0	0
Amount of Gain/(Loss) Recognized in OCI	0	0
Amount of Gain/(Loss) Reclassified From AOCI Into Income	($0.20)	($0.20)

Accounting_for_Derivative_Inst9

Accounting for Derivative Instruments and Hedging Activities - Derivative Volumes Expected to Settle (Detail)	Mar. 31, 2014
	gal
Diesel Fuel Derivatives [Member] | Physical [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Diesel Fuel Derivatives [Member] | Financial [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	1,500,000
Diesel Fuel Derivatives [Member] | 2014 [Member] | Physical [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Diesel Fuel Derivatives [Member] | 2014 [Member] | Financial [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	1,500,000
Diesel Fuel Derivatives [Member] | 2015 [Member] | Physical [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Diesel Fuel Derivatives [Member] | 2015 [Member] | Financial [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Diesel Fuel Derivatives [Member] | 2016 [Member] | Physical [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Diesel Fuel Derivatives [Member] | 2016 [Member] | Financial [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | Physical [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | Physical [Member] | Tampa Electric Company [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | Financial [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	47,100,000
Natural Gas Contracts [Member] | Financial [Member] | Tampa Electric Company [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	47,100,000
Natural Gas Contracts [Member] | 2014 [Member] | Physical [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | 2014 [Member] | Physical [Member] | Tampa Electric Company [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | 2014 [Member] | Financial [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	26,900,000
Natural Gas Contracts [Member] | 2014 [Member] | Financial [Member] | Tampa Electric Company [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	26,900,000
Natural Gas Contracts [Member] | 2015 [Member] | Physical [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | 2015 [Member] | Physical [Member] | Tampa Electric Company [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | 2015 [Member] | Financial [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	18,500,000
Natural Gas Contracts [Member] | 2015 [Member] | Financial [Member] | Tampa Electric Company [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	18,500,000
Natural Gas Contracts [Member] | 2016 [Member] | Physical [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | 2016 [Member] | Financial [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	1,700,000
Natural Gas Contracts [Member] | 2016 [Member] | Physical [Member] | Tampa Electric Company [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	0
Natural Gas Contracts [Member] | 2016 [Member] | Financial [Member] | Tampa Electric Company [Member]	'
Derivative [Line Items]	'
Derivative, Nonmonetary Notional Amount	1,700,000

Recovered_Sheet1

Accounting for Derivative Instruments and Hedging Activities - Fair Value of Overall Contractual Contingent Liability Positions (Detail) (USD $)	Mar. 31, 2014
In Millions, unless otherwise specified
Derivative Instruments And Hedging Activities Disclosure [Abstract]	'
Fair Value Asset/ (Liability)	($0.10)
Derivative Exposure Asset/ (Liability)	-0.1
Posted Collateral	$0

Fair_Value_Measurements_Schedu

Fair Value Measurements - Schedule of Recurring Fair Value Measurements (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	$15.80	$10
Total Swap Liabilities	0.2	0.3
Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.8	10
Total Swap Liabilities	0.2	0.3
Natural Gas Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Diesel Fuel Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0.1	0.2
Total Swap Liabilities	0.1	0.1
Level 1 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Level 1 [Member] | Natural Gas Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Level 1 [Member] | Diesel Fuel Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Level 2 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.8	10
Total Swap Liabilities	0.2	0.3
Level 2 [Member] | Natural Gas Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Level 2 [Member] | Diesel Fuel Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0.1	0.2
Total Swap Liabilities	0.1	0.1
Level 3 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Level 3 [Member] | Natural Gas Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Level 3 [Member] | Diesel Fuel Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Tampa Electric Company [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Tampa Electric Company [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Tampa Electric Company [Member] | Natural Gas Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Tampa Electric Company [Member] | Level 1 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Tampa Electric Company [Member] | Level 1 [Member] | Natural Gas Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Tampa Electric Company [Member] | Level 2 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Tampa Electric Company [Member] | Level 2 [Member] | Natural Gas Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Tampa Electric Company [Member] | Level 3 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Tampa Electric Company [Member] | Level 3 [Member] | Natural Gas Derivatives [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	$0	$0

Fair_Value_Measurements_Additi

Fair Value Measurements - Additional Information (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value Assets Liabilities Measured On Recurring Basis [Line Items]	'	'
Total Swap Assets	$15.80	$10
Total Swap Liabilities	0.2	0.3
Fair Value, Measurements, Recurring [Member]	'	'
Fair Value Assets Liabilities Measured On Recurring Basis [Line Items]	'	'
Total Swap Assets	15.8	10
Total Swap Liabilities	0.2	0.3
Tampa Electric Company [Member]	'	'
Fair Value Assets Liabilities Measured On Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Tampa Electric Company [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value Assets Liabilities Measured On Recurring Basis [Line Items]	'	'
Total Swap Assets	15.7	9.8
Total Swap Liabilities	0.1	0.2
Level 3 [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value Assets Liabilities Measured On Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	0	0
Level 3 [Member] | Tampa Electric Company [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Fair Value Assets Liabilities Measured On Recurring Basis [Line Items]	'	'
Total Swap Assets	0	0
Total Swap Liabilities	$0	$0

Variable_Interest_Entities_Add

Variable Interest Entities - Additional Information (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Long-term Contract for Purchase of Electric Power [Line Items]	'	'
Purchased power	$18.20	$14.60
Tampa Electric Company [Member]	'	'
Long-term Contract for Purchase of Electric Power [Line Items]	'	'
Purchased power	18.2	14.6
Power Purchase Agreements [Member] | Variable Interest Entities [Member]	'	'
Long-term Contract for Purchase of Electric Power [Line Items]	'	'
Purchased power	5.9	4.9
Power Purchase Agreements [Member] | Variable Interest Entities [Member] | Tampa Electric Company [Member]	'	'
Long-term Contract for Purchase of Electric Power [Line Items]	'	'
Purchased power	$5.90	$4.90
Minimum [Member]	'	'
Long-term Contract for Purchase of Electric Power [Line Items]	'	'
Multiple PPAs range	117	'
Minimum [Member] | Tampa Electric Company [Member]	'	'
Long-term Contract for Purchase of Electric Power [Line Items]	'	'
Multiple PPAs range	117	'
Maximum [Member]	'	'
Long-term Contract for Purchase of Electric Power [Line Items]	'	'
Multiple PPAs range	160	'
Maximum [Member] | Tampa Electric Company [Member]	'	'
Long-term Contract for Purchase of Electric Power [Line Items]	'	'
Multiple PPAs range	160	'

Discontinued_Operations_Compon

Discontinued Operations - Components of Discontinued Operations (Detail) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2013
			TECO Guatemala [Member]	TECO Guatemala [Member]
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]	'	'	'	'
Revenues	'	'	$0	$0
Income from operations	'	'	5	0.4
Income from discontinued operations	5	0.4	5	0.4
Provision for income taxes	1.9	0.1	1.9	0.1
Income from discontinued operations, net	$3.10	$0.30	$3.10	$0.30

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail) (TECO Guatemala Holdings, LLC v. The Republic of Guatemala [Member], USD $)	0 Months Ended	3 Months Ended
In Millions, unless otherwise specified	Dec. 19, 2013	Mar. 31, 2014
TECO Guatemala Holdings, LLC v. The Republic of Guatemala [Member]	'	'
Subsequent Event [Line Items]	'	'
litigation settlement expenses	$21.10	'
litigation settlement interest	'	'U.S. prime rate plus 2%
litigation settlement amount	$7.50	'
Settlement agreement payment term	'	'120 days after the date of the Award