Consolidated Statements of Income and Comprehensive Income (Parenthetical) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Franchise fees and gross receipts taxes	$ 108.5	$ 111.5	$ 109.3
Tampa Electric Company [Member]
Franchise fees and gross receipts taxes	108.5	111.5	109.3
Tampa Electric Company [Member] | Electric [Member]
Franchise fees and gross receipts taxes	88.0	91.1	85.6
Tampa Electric Company [Member] | Gas [Member]
Franchise fees and gross receipts taxes	$ 20.5	$ 20.4	$ 23.7