Commitments and Contingencies (Long-term Purchase Commitment) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
NEER Segment
Required capacity and/or minimum payments [Abstract]
Remainder of 2021	$ 1,470		$ 1,470
2022	2,935		2,935
2023	350		350
2024	245		245
2025	150		150
Thereafter	1,780		1,780
Commitment to invest	210		210
Joint Obligations Remainder Current Year	115		115
Joint Obligations Second Year	85		85
Joint Obligations Third Year	35		35
Joint Obligations Fourth Year	10		10
Joint Obligations Fifth Year	5		5
Joint Obligations After Fifth Year	5		5
Contract Group 1 [Member] | NEER Segment
Long-term Purchase Commitment [Line Items]
Commitment amount included in capital expenditures	4,100		4,100
Mountain Valley Pipeline [Member] | NEER Segment
Required capacity and/or minimum payments [Abstract]
2022	25		25
2023	70		70
2024	70		70
2025	70		70
Thereafter	$ 1,155		$ 1,155
Equity method investment, ownership percentage	31.50%		31.50%
FPL [Member]
Required capacity and/or minimum payments [Abstract]
Remainder of 2021	$ 265		$ 265
2022	995		995
2023	980		980
2024	955		955
2025	900		900
Thereafter	9,385		9,385
Related Party Transaction, Amounts of Transaction	105	$ 104	314	$ 280
FPL [Member] | Sabal Trail and Florida Southeast Connection [Member] | Natural Gas, Including Transportation And Storage, Contract Minimum Payments [Member]
Required capacity and/or minimum payments [Abstract]
Remainder of 2021	105		105
2022	415		415
2023	410		410
2024	410		410
2025	405		405
Thereafter	6,360		6,360
Consolidation, Eliminations [Member] | FPL [Member]
Required capacity and/or minimum payments [Abstract]
Related Party Transaction, Amounts of Transaction	$ 26	$ 27	$ 79	$ 81