Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2016

Schedule of Recurring Fair Value Measurements

Recurring Fair Value Measures
	As of Mar. 31, 2016
(millions)	Level 1		Level 2		Level 3		Total
Liabilities
Natural gas derivatives	$	0.0	$	23.1	$	0.0	$	23.1
	As of Dec. 31, 2015
(millions)	Level 1		Level 2		Level 3		Total
Assets
Natural gas derivatives	$	0.0	$	0.2	$	0.0	$	0.2
Liabilities
Natural gas derivatives	$	0.0	$	26.2	$	0.0	$	26.2

Tampa Electric Company [Member]

Schedule of Recurring Fair Value Measurements

Recurring Derivative Fair Value Measures
	As of Mar. 31, 2016
(millions)	Level 1		Level 2		Level 3		Total
Liabilities
Natural gas swaps	$	0.0	$	23.0	$	0.0	$	23.0
	As of Dec. 31, 2015
(millions)	Level 1		Level 2		Level 3		Total
Liabilities
Natural gas swaps	$	0.0	$	26.2	$	0.0	$	26.2