Consolidated Statements of Retained Earnings (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Beginning Balance	$ 541.7
Add: Net income	197.7	212.7	272.6
Deduct: Cash dividends on capital stock - common	191.2	190.4	183.2
Ending Balance	548.3	541.7
Tampa Electric Company [Member]
Beginning Balance	304.6	305.7	311.1
Add: Net income	225.6	227.2	235.3
Retained Earning, Gross	530.2	532.9	546.4
Deduct: Cash dividends on capital stock - common	222.1	228.3	240.7
Ending Balance	$ 308.1	$ 304.6	$ 305.7