Consolidated Statements of Capitalization - Long-Term Debt - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Long-term debt, total	$ 3,775	$ 3,425
Unamortized debt discount, net	(11)	(12)
Debt issuance costs	(30)	(27)
Long-term debt, carrying amount	3,734	3,386
Less amount due within one year	0	250
Total long-term debt	3,734	3,136
Long-term debt, fair value	3,234	4,036
Tampa Electric [Member]
Debt Instrument [Line Items]
Long-term debt, total	$ 3,205	2,905
Tampa Electric [Member] \| 3.88% Notes [Member]
Debt Instrument [Line Items]
Due	2024
Long-term debt, total	$ 263	0
Tampa Electric [Member] \| 2.60% Notes [Member]
Debt Instrument [Line Items]
Due	2022
Long-term debt, total	$ 0	225
Tampa Electric [Member] \| 2.40% Notes [Member]
Debt Instrument [Line Items]
Due	2031
Long-term debt, total	$ 285	285
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	285
Tampa Electric [Member] \| 5.00% Notes [Member]
Debt Instrument [Line Items]
Due	2052
Long-term debt, total	$ 262	0
PGS [Member]
Debt Instrument [Line Items]
Long-term debt, total	$ 570	520
PGS [Member] \| 3.88% Notes [Member]
Debt Instrument [Line Items]
Due	2024
Long-term debt, total	$ 38	0
PGS [Member] \| 2.60% Notes [Member]
Debt Instrument [Line Items]
Due	2022
Long-term debt, total	$ 0	25
PGS [Member] \| 2.40% Notes [Member]
Debt Instrument [Line Items]
Due	2031
Long-term debt, total	$ 115	115
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	115
PGS [Member] \| 5.00% Notes [Member]
Debt Instrument [Line Items]
Due	2052
Long-term debt, total	$ 37	$ 0

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- Definition

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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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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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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