Consolidated Statements of Capitalization - Long-Term Debt - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Long-term debt, total	$ 3,425	$ 2,903
Unamortized debt discount, net	(12)	(10)
Debt issuance costs	(27)	(21)
Long-term debt, carrying amount	3,386	2,872
Less amount due within one year	250	278
Total long-term debt	3,136	2,594
Long-term debt, fair value	4,036	3,597
Tampa Electric [Member]
Debt Instrument [Line Items]
Long-term debt, total	2,905	2,566
Long-term debt, carrying amount	$ 2,905
Tampa Electric [Member] \| 5.40% Notes [Member]
Debt Instrument [Line Items]
Due	2021
Long-term debt, total	$ 0	231
Tampa Electric [Member] \| 2.60% Notes [Member]
Debt Instrument [Line Items]
Due	2022
Long-term debt, total	$ 225	225
Tampa Electric [Member] \| 2.40% Notes [Member]
Debt Instrument [Line Items]
Due	2031
Long-term debt, total	$ 285	0
Tampa Electric [Member] \| 6.55% Notes [Member]
Debt Instrument [Line Items]
Due	2036
Long-term debt, total	$ 250	250
Tampa Electric [Member] \| 6.15% Notes [Member]
Debt Instrument [Line Items]
Due	2037
Long-term debt, total	$ 190	190
Tampa Electric [Member] \| 4.10% Notes [Member]
Debt Instrument [Line Items]
Due	2042
Long-term debt, total	$ 250	250
Tampa Electric [Member] \| 4.35% Notes [Member]
Debt Instrument [Line Items]
Due	2044
Long-term debt, total	$ 290	290
Tampa Electric [Member] \| 4.20% Notes [Member]
Debt Instrument [Line Items]
Due	2045
Long-term debt, total	$ 230	230
Tampa Electric [Member] \| 4.30% Notes [Member]
Debt Instrument [Line Items]
Due	2048
Long-term debt, total	$ 275	275
Tampa Electric [Member] \| 4.45% Notes [Member]
Debt Instrument [Line Items]
Due	2049
Long-term debt, total	$ 350	350
Tampa Electric [Member] \| 3.63% Notes [Member]
Debt Instrument [Line Items]
Due	2050
Long-term debt, total	$ 275	275
Tampa Electric [Member] \| 3.45% Notes [Member]
Debt Instrument [Line Items]
Due	2051
Long-term debt, total	$ 285	0
PGS [Member]
Debt Instrument [Line Items]
Long-term debt, total	520	337
Long-term debt, carrying amount	$ 520
PGS [Member] \| 5.40% Notes [Member]
Debt Instrument [Line Items]
Due	2021
Long-term debt, total	$ 0	47
PGS [Member] \| 2.60% Notes [Member]
Debt Instrument [Line Items]
Due	2022
Long-term debt, total	$ 25	25
PGS [Member] \| 2.40% Notes [Member]
Debt Instrument [Line Items]
Due	2031
Long-term debt, total	$ 115	0
PGS [Member] \| 6.15% Notes [Member]
Debt Instrument [Line Items]
Due	2037
Long-term debt, total	$ 60	60
PGS [Member] \| 4.10% Notes [Member]
Debt Instrument [Line Items]
Due	2042
Long-term debt, total	$ 50	50
PGS [Member] \| 4.35% Notes [Member]
Debt Instrument [Line Items]
Due	2044
Long-term debt, total	$ 10	10
PGS [Member] \| 4.20% Notes [Member]
Debt Instrument [Line Items]
Due	2045
Long-term debt, total	$ 20	20
PGS [Member] \| 4.30% Notes [Member]
Debt Instrument [Line Items]
Due	2048
Long-term debt, total	$ 75	75
PGS [Member] \| 4.45% Notes [Member]
Debt Instrument [Line Items]
Due	2049
Long-term debt, total	$ 25	25
PGS [Member] \| 3.63% Notes [Member]
Debt Instrument [Line Items]
Due	2050
Long-term debt, total	$ 25	25
PGS [Member] \| 3.45% Notes [Member]
Debt Instrument [Line Items]
Due	2051
Long-term debt, total	$ 115	$ 0

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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