Short-Term Debt - Additional Information (Detail) (USD $)	12 Months Ended			0 Months Ended		12 Months Ended		0 Months Ended		12 Months Ended				12 Months Ended			0 Months Ended		12 Months Ended						12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 17, 2013 Revolving Credit Facility [Member]	Feb. 15, 2014 Subsequent Event [Member]	Feb. 15, 2014 Subsequent Event [Member] 1-year Accounts Receivable Facility [Member]	Dec. 31, 2013 TECO Energy [Member]	Dec. 31, 2013 TECO Energy [Member] Revolving Credit Facility [Member]	Dec. 17, 2013 TECO Finance [Member]	Dec. 17, 2013 Tampa Electric Company [Member]	Dec. 31, 2013 Tampa Electric Company [Member]	Dec. 31, 2012 Tampa Electric Company [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 1-year Accounts Receivable Facility [Member]	Dec. 31, 2012 Tampa Electric Company [Member] 1-year Accounts Receivable Facility [Member]	Dec. 31, 2013 Tampa Electric Company [Member] Amended And Restated Credit Agreement [Member]	Dec. 17, 2013 Tampa Electric Company [Member] Amended And Restated Credit Agreement [Member]	Dec. 17, 2013 Tampa Electric Company [Member] Previous Agreement [Member]	Feb. 15, 2014 Tampa Electric Company [Member] Subsequent Event [Member]	Feb. 15, 2014 Tampa Electric Company [Member] Subsequent Event [Member] 1-year Accounts Receivable Facility [Member]	Dec. 31, 2013 Minimum [Member]	Dec. 31, 2013 Minimum [Member] TECO Energy [Member]	Dec. 31, 2013 Minimum [Member] Tampa Electric Company [Member]	Dec. 31, 2013 Maximum [Member]	Dec. 31, 2013 Maximum [Member] TECO Energy [Member]	Dec. 31, 2013 Maximum [Member] TECO Energy [Member] Revolving Credit Facility [Member]	Dec. 31, 2013 Maximum [Member] Tampa Electric Company [Member]
Line of Credit Facility [Line Items]
Commitment fees, percentage					0.70%												0.70%		0.125%		0.125%	0.25%			0.25%
Outstanding borrowings	$ 84,000,000	$ 0								$ 84,000,000	$ 0	$ 78,000,000	$ 0
Weighted-average interest rate	0.56%									0.56%
Amended credit facility	675,000,000	675,000,000	200,000,000		150,000,000			200,000,000	200,000,000	475,000,000	475,000,000	150,000,000	150,000,000		325,000,000	200,000,000	150,000,000	150,000,000
Debt instrument maturity date				Feb. 13, 2015	Feb. 13, 2015									Oct. 25, 2016 to Dec. 17, 2018			Feb. 13, 2015
Amended maturity date of credit facility	Dec. 17, 2018									Dec. 17, 2018										Oct. 25, 2016			Dec. 17, 2018
Interest rate description						TECO Finance to borrow funds at an interest rate equal to the London interbank deposit rate plus a margin; (iv) as an alternative to the above interest rate, allows TECO Finance to borrow funds at an interest rate equal to a margin plus the higher of the JPMorgan Chase Bank's prime rate, the federal funds rate plus 50 basis points, or the London interbank deposit rate plus 1.00%.			Tampa Electric Company to borrow funds at an interest rate equal to a margin plus the higher of Citibank's prime rate, the federal funds rate plus 50 basis points, or the London interbank deposit rate plus 1.00%
Increase of credit facility								$ 100,000,000	$ 175,000,000
Normal capitalization ratio							0.65																	0.70