Income Taxes - Reconciliation Between the Effective Income Tax Rates and the Applicable Statutory Rate (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Effective Income Tax Rate Reconciliation [Line Items]
Statutory federal income tax rate	21.00%	21.00%	21.00%	21.00%
Increases (reductions) resulting from:
State income taxes - net of federal income tax benefit	2.00%	6.50%	3.00%	4.70%
Taxes attributable to noncontrolling interests	1.60%	2.20%	1.80%	2.40%
PTCs and ITCs - NEER	(5.20%)	(5.90%)	(6.30%)	(1.90%)
Amortization of deferred regulatory credit	(9.20%)	(3.20%)	(7.70%)	(1.00%)
Other - net	(0.40%)	4.20%	(1.60%)	(0.60%)
Effective income tax rate	9.80%	24.80%	10.20%	24.60%
Tax Cuts and Jobs Act of 2017, income tax expense (benefit)				$ 125
FPL [Member]
Effective Income Tax Rate Reconciliation [Line Items]
Statutory federal income tax rate	21.00%	21.00%	21.00%	21.00%
Increases (reductions) resulting from:
State income taxes - net of federal income tax benefit	1.60%	4.30%	3.00%	4.30%
Taxes attributable to noncontrolling interests	0.00%	0.00%	0.00%	0.00%
PTCs and ITCs - NEER	0.00%	0.00%	0.00%	0.00%
Amortization of deferred regulatory credit	(15.60%)	(3.70%)	(9.60%)	(4.20%)
Other - net	0.10%	0.30%	(0.20%)	(0.50%)
Effective income tax rate	7.10%	21.90%	14.20%	20.60%
Income tax benefits related to the amortization of deferred regulatory credits	$ 83		$ 83
Amortization period			10 years

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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