Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Accounting Policies [Abstract]

Estimated Useful Lives of Depreciable Property

Other TECO Energy subsidiaries compute depreciation primarily by the straight-line method at annual rates that amortize the original cost, less net salvage value, of depreciable property over the following estimated useful lives:

Asset	Estimated Useful Lives
Building and improvements	40 years
Office equipment and furniture	4 - 7 years
Computer software	3 - 15 years

Schedule of Fuel Inventory

Fuel Inventory	Dec. 31,		Dec. 31,
(millions)	2015		2014
TEC	$	105.6	$	85.2
NMGC		7.8		11.2
Total	$	113.4	$	96.4