Income Taxes - Reconciliation of Effective Income Tax Rate (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating Loss Carryforwards [Line Items]
Statutory federal income tax rate	21.00%	21.00%	21.00%
Increases (reductions) resulting from:
State income taxes - net of federal income tax benefit(a)	2.80%	3.40%	4.20%
Taxes attributable to noncontrolling interests	4.80%	2.10%	2.50%
PTCs and ITCs - NEER	(11.80%)	(7.20%)	(3.00%)
Amortization of deferred regulatory credit(b)	7.20%	6.20%	(1.80%)
Foreign operations(c)			(0.80%)
Other - net	(5.40%)	(1.40%)	(0.70%)
Effective income tax rate (in hundredths)	1.80%	11.70%	21.40%
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent	(2.40%)	0.00%
State [Member]
Increases (reductions) resulting from:
Deferred Income Taxes and Tax Credits		$ 48
FPL[Member]
Operating Loss Carryforwards [Line Items]
Statutory federal income tax rate	21.00%	21.00%	21.00%
Increases (reductions) resulting from:
State income taxes - net of federal income tax benefit(a)	4.10%	3.50%	4.50%
Taxes attributable to noncontrolling interests	0.00%	0.00%	0.00%
PTCs and ITCs - NEER	0.00%	0.00%	0.00%
Amortization of deferred regulatory credit(b)	5.00%	8.10%	(5.00%)
Foreign operations(c)			0.00%
Other - net	(1.40%)	(0.50%)	(0.60%)
Effective income tax rate (in hundredths)	18.70%	15.90%	19.90%
Amortization of deferred regulatory credit		$ 83
Amortization Of Excess Deferred Income Taxes		$ 870
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent	0.00%	0.00%