Consolidated Condensed Balance Sheets (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 152.8	$ 200.5
Receivables, less allowance for uncollectibles	347.1	282.7
Inventories, at average cost
Fuel	119.6	123.6
Materials and supplies	83.0	82.1
Regulatory assets	40.9	70.3
Derivative assets	0.2	0
Income tax receivables	0.8	0.4
Deferred income taxes	28.5	63.3
Prepayments and other current assets	38.1	33.9
Total current assets	811.0	856.8
Property, plant and equipment
Electric	6,862.5	6,655.8
Gas	1,284.3	1,228.3
Construction work in progress	356.6	336.1
Other property	447.3	443.8
Property, plant and equipment, at original costs	8,950.7	8,664.0
Accumulated depreciation	(2,869.8)	(2,695.5)
Total property, plant and equipment, net	6,080.9	5,968.5
Other assets
Regulatory assets	370.5	382.6
Derivative assets	0	0.2
Deferred charges and other assets	131.7	126.8
Total other assets	502.2	509.6
Total assets	7,394.1	7,334.9
Current liabilities
Long-term debt due within one year	83.3	0
Accounts payable	241.3	232.8
Customer deposits	164.5	162.9
Regulatory liabilities	81.3	105.6
Derivative liabilities	5.2	14.6
Interest accrued	55.4	33.2
Taxes accrued	79.3	32.1
Other	17.4	19.9
Total current liabilities	727.7	601.1
Other liabilities
Deferred income taxes	338.0	277.9
Investment tax credits	9.4	9.7
Regulatory liabilities	632.7	631.4
Derivative liabilities	1.5	0.6
Deferred credits and other liabilities	523.1	549.7
Long-term debt, less amount due within one year	2,837.8	2,972.7
Total other liabilities	4,342.5	4,442.0
Commitments and Contingencies
Capital
Common equity	217.3	216.6
Additional paid in capital	1,578.8	1,564.5
Retained earnings	554.1	541.7
Accumulated other comprehensive loss	(26.3)	(31.0)
Total capital	2,323.9	2,291.8
Long-term debt, less amount due within one year	2,837.8	2,972.7
Total liabilities and capital	7,394.1	7,334.9
Tampa Electric Company [Member]
Current assets
Cash and cash equivalents	14.3	45.2
Receivables, less allowance for uncollectibles	275.3	213.8
Inventories, at average cost
Fuel	90.2	89.1
Materials and supplies	73.9	72.4
Regulatory assets	40.9	70.3
Derivative assets	0.1	0
Income tax receivables	0	22.1
Deferred income taxes	22.6	20.0
Prepayments and other current assets	16.6	11.5
Total current assets	533.9	544.4
Property, plant and equipment
Electric	6,862.5	6,654.5
Gas	1,227.9	1,171.9
Construction work in progress	351.7	335.0
Property, plant and equipment, at original costs	8,442.1	8,161.4
Accumulated depreciation	(2,528.1)	(2,373.6)
Public utilities, property, plant and equipment, net	5,914.0	5,787.8
Other property, net	8.1	7.3
Total property, plant and equipment, net	5,922.1	5,795.1
Other assets
Unamortized debt expense	0.1	16.1
Regulatory assets	370.5	382.6
Derivative assets	0	0.2
Other	21.3	6.2
Total other assets	391.9	405.1
Total assets	6,847.9	6,744.6
Current liabilities
Long-term debt due within one year	83.3	0
Accounts payable	192.7	188.6
Customer deposits	164.5	163.0
Regulatory liabilities	81.3	105.6
Derivative liabilities	4.9	14.1
Interest accrued	37.3	17.3
Taxes accrued	81.2	13.7
Other	11.8	11.8
Total current liabilities	657.0	514.1
Other liabilities
Deferred income taxes	1,042.7	980.9
Investment tax credits	9.4	9.7
Regulatory liabilities	632.7	631.4
Derivative liabilities	1.4	0.2
Other	389.6	409.4
Long-term debt, less amount due within one year	1,797.6	1,932.6
Total other liabilities	2,075.8	2,031.6
Commitments and Contingencies
Capital
Common equity	1,990.4	1,970.4
Retained earnings	335.1	304.6
Accumulated other comprehensive loss	(8.0)	(8.7)
Total capital	2,317.5	2,266.3
Long-term debt, less amount due within one year	1,797.6	1,932.6
Total capitalization	4,115.1	4,198.9
Total liabilities and capital	$ 6,847.9	$ 6,744.6