Revenue - Summary of Disaggregates TEC Revenue by Major Source (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Disaggregation Of Revenue [Line Items]
Total electric revenue	$ 2,637	$ 2,519	$ 2,170
Total gas revenue	0	650	525
Total revenue	2,637	3,169	2,695
Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	1,711	1,381	1,156
Total gas revenue		229	212
Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	803	666	602
Total gas revenue		200	191
Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	203	176	172
Total gas revenue		31	25
Regulatory Deferrals [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(387)	(21)	(6)
Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(2)	9	(2)
Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	309	308	248
Total gas revenue		190	97
Eliminations [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		(4)	(4)
Total gas revenue		(6)	(3)
Total revenue		(10)	(7)
Eliminations [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Total gas revenue		0	0
Eliminations [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Total gas revenue		0	0
Eliminations [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Total gas revenue		0	0
Eliminations [Member] | Regulatory Deferrals [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Eliminations [Member] | Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Eliminations [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		(4)	(4)
Total gas revenue		(6)	(3)
Tampa Electric [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	2,637	2,523	2,174
Total gas revenue		0	0
Total revenue	2,637	2,523	2,174
Tampa Electric [Member] | Operating Segments [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	1,711	1,381	1,156
Total gas revenue		0	0
Tampa Electric [Member] | Operating Segments [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	803	666	602
Total gas revenue		0	0
Tampa Electric [Member] | Operating Segments [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	203	176	172
Total gas revenue		0	0
Tampa Electric [Member] | Operating Segments [Member] | Regulatory Deferrals [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(387)	(21)	(6)
Tampa Electric [Member] | Operating Segments [Member] | Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	(2)	9	(2)
Tampa Electric [Member] | Operating Segments [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue	$ 309	312	252
Total gas revenue		0	0
PGS [Member] | Operating Segments [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Total gas revenue		656	528
Total revenue		656	528
PGS [Member] | Operating Segments [Member] | Residential [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Total gas revenue		229	212
PGS [Member] | Operating Segments [Member] | Commercial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Total gas revenue		200	191
PGS [Member] | Operating Segments [Member] | Industrial [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Total gas revenue		31	25
PGS [Member] | Operating Segments [Member] | Regulatory Deferrals [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
PGS [Member] | Operating Segments [Member] | Unbilled Revenue [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
PGS [Member] | Operating Segments [Member] | Other [Member]
Disaggregation Of Revenue [Line Items]
Total electric revenue		0	0
Total gas revenue		$ 196	$ 100