Employee Postretirement Benefits (Tables)

3 Months Ended

Mar. 31, 2016

Compensation And Retirement Disclosure [Abstract]

Schedule of Net Periodic Benefit Cost

Included in the table below is the periodic expense for pension and other postretirement benefits offered by the company. Amounts disclosed for pension benefits include the amounts related to the qualified pension plan and the non-qualified, non-contributory SERP.

Pension Expense
(millions)	Pension Benefits						Other Postretirement Benefits
Three months ended Mar. 31,	2016			2015			2016			2015
Components of net periodic benefit expense
Service cost	$	4.4		$	4.5		$	0.5		$	0.6
Interest cost		8.1			7.4			2.2			2.0
Expected return on assets		(11.3	)		(10.8	)		(0.3	)		(0.3	)
Amortization of:
Prior service (benefit) cost		0.0			(0.1	)		(0.6	)		(0.6	)
Actuarial loss		3.4			3.4			0.0			0.0
Regulatory asset		0.0			0.0			0.2			0.3
Net pension expense recognized in the    TECO Energy Consolidated Condensed Statements of Income	$	4.6		$	4.4		$	2.0		$	2.0