Long Term Debt - Schedule of Long Term Debt Outstanding (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Mar. 31, 2008 Tampa Electric Company [Member] Variable Rate Bonds Repurchased In 2008 [Member]	Sep. 30, 2013 Tampa Electric Company [Member] Refunding Bonds Repurchased In 2013 [Member]	Mar. 31, 2011 Tampa Electric Company [Member] Term Rate Bonds Repurchased In 2012 [Member]	Mar. 31, 2012 Tampa Electric Company [Member] Refunding Bonds Repurchased In 2012 [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 5.65% Refunding bonds [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 5.15% Refunding bonds [Member]	Dec. 31, 2012 Tampa Electric Company [Member] 5.15% Refunding bonds [Member]	Sep. 30, 2012 Tampa Electric Company [Member] 5.15% Refunding bonds [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 1.5% term rate bonds repurchased in 2011 [Member]	Mar. 31, 2011 Tampa Electric Company [Member] 1.5% term rate bonds repurchased in 2011 [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 5.0% Refunding bonds [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 6.25% Notes [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 6.1% Notes [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 5.4% Notes [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 2.6% Notes [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 6.55% Notes [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 6.15% Notes [Member]	Dec. 31, 2013 Tampa Electric Company [Member] 4.1% Notes [Member]	Dec. 31, 2013 TECO Finance [Member] 6.75% Notes [Member]	Dec. 31, 2013 TECO Finance [Member] 4.00% Notes [Member]	Dec. 31, 2013 TECO Finance [Member] 6.752% Notes [Member]	Dec. 31, 2013 TECO Finance [Member] 5.15% Notes [Member]	Dec. 31, 2013 PGS [Member] 6.1% Notes [Member]	Dec. 31, 2013 PGS [Member] 5.4% Notes [Member]	Dec. 31, 2013 PGS [Member] 2.6% Notes [Member]	Dec. 31, 2013 PGS [Member] 6.15% Notes [Member]	Dec. 31, 2013 PGS [Member] 4.1% Notes [Member]
Debt Instrument [Line Items]
Effective interest rate					5.90%		5.40%				0.00%	6.30%	6.00%	5.40%	2.70%	6.60%	6.20%	4.20%	6.90%	4.20%	7.30%	5.30%	7.00%	5.40%	2.70%	6.20%	4.20%
Stated interest rate					5.65%	5.15%			1.50%		5.00%	6.25%	6.10%	5.40%	2.60%	6.55%	6.15%	4.10%	6.75%	4.00%	6.572%	5.15%	6.10%	5.40%	2.60%	6.15%	4.10%
Repurchased bonds, par amount	$ 20.0	$ 51.6	$ 75.0	$ 86.0				$ 51.6		$ 75.0