Long Term Debt - Schedule of Long Term Debt Outstanding (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Long-term debt, total	$ 2,923.8	$ 2,975.4
Unamortized debt discount, net	(2.7)	(2.7)
Long-term debt, carrying amount	2,921.1	2,972.7
Less amount due within one year	83.3	0
Total long-term debt	2,837.8	2,972.7
Tampa Electric Company [Member]
Debt Instrument [Line Items]
Long-term debt, total	1,650.9	1,702.5
Less amount due within one year	83.3	0
Total long-term debt	1,797.5	1,932.6
TECO Finance [Member]
Debt Instrument [Line Items]
Long-term debt, total	1,041.2	1,041.2
PGS [Member]
Debt Instrument [Line Items]
Long-term debt, total	231.7	231.7
Variable Rate Bonds Repurchased In 2008 [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2020
Long-term debt, total	0	0
6.75% Notes [Member] | TECO Finance [Member]
Debt Instrument [Line Items]
Due	2015
Long-term debt, total	191.2	191.2
4.00% Notes [Member] | TECO Finance [Member]
Debt Instrument [Line Items]
Due	2016
Long-term debt, total	250.0	250.0
6.752% Notes [Member] | TECO Finance [Member]
Debt Instrument [Line Items]
Due	2017
Long-term debt, total	300.0	300.0
5.15% Notes [Member] | TECO Finance [Member]
Debt Instrument [Line Items]
Due	2020
Long-term debt, total	300.0	300.0
5.65% Refunding bonds [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2018
Long-term debt, total	54.2	54.2
5.15% Refunding bonds [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2025
Long-term debt, total	0	51.6
1.5% term rate bonds repurchased in 2011 [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2030
Long-term debt, total	0	0
5.0% Refunding bonds [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2034
Long-term debt, total	0	0
6.25% Notes [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Maturity range start	2014
Due	2016
Long-term debt, total	250.0	250.0
6.1% Notes [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2018
Long-term debt, total	200.0	200.0
6.1% Notes [Member] | PGS [Member]
Debt Instrument [Line Items]
Due	2018
Long-term debt, total	50.0	50.0
5.4% Notes [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2021
Long-term debt, total	231.7	231.7
5.4% Notes [Member] | PGS [Member]
Debt Instrument [Line Items]
Due	2021
Long-term debt, total	46.7	46.7
2.6% Notes [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2022
Long-term debt, total	225.0	225.0
2.6% Notes [Member] | PGS [Member]
Debt Instrument [Line Items]
Due	2022
Long-term debt, total	25.0	25.0
6.55% Notes [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2036
Long-term debt, total	250.0	250.0
6.15% Notes [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Due	2037
Long-term debt, total	190.0	190.0
6.15% Notes [Member] | PGS [Member]
Debt Instrument [Line Items]
Due	2037
Long-term debt, total	60.0	60.0
4.1% Notes [Member]
Debt Instrument [Line Items]
Due	2042
4.1% Notes [Member] | Tampa Electric Company [Member]
Debt Instrument [Line Items]
Long-term debt, total	250.0	250.0
4.1% Notes [Member] | PGS [Member]
Debt Instrument [Line Items]
Due	2042
Long-term debt, total	$ 50.0	$ 50.0