Commitments and Contingencies - Schedule of Long-term Commitments (Parenthetical) (Detail) $ in Millions	Dec. 31, 2022 USD ($)
Other Commitments [Line Items]
Total future minimum payments	$ 4,063
Gas Transportation [Member] | PGS and SeaCoast [Member]
Other Commitments [Line Items]
Total future minimum payments	106
Fuel and Gas Supply [Member]
Other Commitments [Line Items]
Total future minimum payments	448
Fuel and Gas Supply [Member] | Tampa Electric [Member]
Other Commitments [Line Items]
Total future minimum payments	45
Transportation [Member]
Other Commitments [Line Items]
Total future minimum payments	3,160
Transportation [Member] | Tampa Electric [Member]
Other Commitments [Line Items]
Total future minimum payments	$ 1,518