Equity (Accumulated Other Comprehensive Income) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ 45,114	$ 41,574	$ 44,929	$ 41,360
Other comprehensive income before reclassifications	(14)	11
Amounts reclassified from AOCI	0	2
Total other comprehensive income (loss), net of tax	(14)	13	(2)	6
Accumulated Other Comprehensive Income (Loss), Net of Tax	(94)	(153)	(94)	(153)	$ (92)
Attributable to noncontrolling interests	(8)		(8)
Attributable to NEE	(86)		(86)
Ending Balance	44,647	42,062	44,647	42,062
Accumulated Gain (Loss), Cash Flow Hedge, Including Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	12	1	8	(27)
Other comprehensive income before reclassifications			0	0
Amounts reclassified from AOCI			4	7
Total other comprehensive income (loss), net of tax			4	7
Impact of disposal of a business				23
Ending Balance	12	3	12	3
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Including Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	11	16	20	11
Other comprehensive income before reclassifications			(9)	9
Amounts reclassified from AOCI			(3)	(2)
Total other comprehensive income (loss), net of tax			(12)	7
Impact of disposal of a business				0
Ending Balance	8	18	8	18
Accumulated Defined Benefit Plans Adjustment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(73)	(113)	(75)	(114)
Other comprehensive income before reclassifications			0	0
Amounts reclassified from AOCI			3	2
Total other comprehensive income (loss), net of tax			3	2
Impact of disposal of a business
Ending Balance	(72)	(112)	(72)	(112)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(39)	(73)	(49)	(42)
Other comprehensive income before reclassifications			2	(10)
Amounts reclassified from AOCI			0	0
Total other comprehensive income (loss), net of tax			2	(10)
Impact of disposal of a business				(13)
Ending Balance	(47)	(65)	(47)	(65)
Accumulated Other-than-Temporary Impairment Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	4	3	4	3
Other comprehensive income before reclassifications			1	0
Amounts reclassified from AOCI			0	0
Total other comprehensive income (loss), net of tax			1	0
Impact of disposal of a business
Ending Balance	5	3	5	3
AOCI Including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(85)	(166)	(92)	(169)
Other comprehensive income before reclassifications			(6)	(1)
Amounts reclassified from AOCI			4	7
Total other comprehensive income (loss), net of tax			(2)	6
Impact of disposal of a business				10
Ending Balance	(94)	(153)	(94)	(153)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending Balance	0	0	0	0
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending Balance	0	0	0	0
Accumulated Defined Benefit Plans Adjustment Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending Balance	0	0	0	0
Accumulated Foreign Currency Adjustment Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending Balance	(8)	(1)	(8)	(1)
Accumulated Other-than-Temporary Impairment Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending Balance	0	0	0	0
AOCI Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending Balance	(8)	(1)	(8)	(1)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance, attributable to NEE	12	3	12	3
Net Unrealized Gains (Losses) on Available for Sale Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income before reclassifications	(2)	3
Amounts reclassified from AOCI	(1)	(1)
Total other comprehensive income (loss), net of tax	(3)	2
Accumulated Other Comprehensive Income (Loss), Net of Tax	8	18	8	18
Attributable to noncontrolling interests	0		0
Attributable to NEE	8		8
Ending balance, attributable to NEE	8	18	8	18
Defined Benefit Pension and Other Benefits Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income before reclassifications	0	0
Amounts reclassified from AOCI	1	1
Total other comprehensive income (loss), net of tax	1	1
Accumulated Other Comprehensive Income (Loss), Net of Tax	(72)	(112)	(72)	(112)
Attributable to noncontrolling interests	0		0
Attributable to NEE	(72)		(72)
Ending balance, attributable to NEE	(72)	(112)	(72)	(112)
Net Unrealized Gains (Losses) on Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income before reclassifications	(13)	8
Amounts reclassified from AOCI	0	0
Total other comprehensive income (loss), net of tax	(13)	8
Accumulated Other Comprehensive Income (Loss), Net of Tax	(47)	(65)	(47)	(65)
Attributable to noncontrolling interests	(8)		(8)
Attributable to NEE	(39)		(39)
Ending balance, attributable to NEE	(39)	(64)	(39)	(64)
Accumulated Other-than-Temporary Impairment Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Ending balance, attributable to NEE	5	3	5	3
AOCI Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(85)	(163)	(92)	(169)
Total other comprehensive income (loss), net of tax	(9)	11	(2)	7
Ending Balance	(94)	(152)	(94)	(152)
Ending balance, attributable to NEE	(86)	(152)	(86)	(152)
Net Unrealized Gains (Losses) on Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income before reclassifications	0	0
Amounts reclassified from AOCI	0	2
Total other comprehensive income (loss), net of tax	0	2
Accumulated Other Comprehensive Income (Loss), Net of Tax	12	3	12	3
Attributable to noncontrolling interests	0		0
Attributable to NEE	12		12
Other Comprehensive Income (Loss) Related to Equity Method Investees
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other comprehensive income before reclassifications	1	0
Amounts reclassified from AOCI	0	0
Total other comprehensive income (loss), net of tax	1	0
Accumulated Other Comprehensive Income (Loss), Net of Tax	5	$ 3	5	$ 3
Attributable to noncontrolling interests	0		0
Attributable to NEE	$ 5		$ 5