Related Party Transactions - Schedule of Related Parties (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Related Party Transaction [Line Items]
Natural gas sales to/(from) affiliates	$ 33	$ 83
Services to/(from) affiliates	12	(2)
Dividends to TECO Energy	91	85
Equity contributions from TECO Energy	100	175
PGS [Member]
Related Party Transaction [Line Items]
Interest income from PGS	8	0
Note receivable from PGS	805		$ 0
Interest receivable	12		0
Affiliate [Member]
Related Party Transaction [Line Items]
Accounts receivable excluding asset management agreements	7		5
Taxes receivable	9		10
Accounts payable	18		31
Note payable to TECO Energy	195		195
Interest payable to TECO Energy	1		0
Emera Energy Services Inc [Member]
Related Party Transaction [Line Items]
Accounts receivable related to asset management agreements to Emera Energy Services Inc.	5		$ 7
TECO Energy [Member]
Related Party Transaction [Line Items]
Interest expense to TECO Energy	3	0
Dividends to TECO Energy	91	85
Equity contributions from TECO Energy	$ 100	$ 175

Accounts receivable excluding asset management agreements.

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Natural gas sales to (from) affiliates.

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