Segment Information - Schedule of Segment Information (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013
Segment Reporting Information [Line Items]
Operating revenues	$ 4,069	$ 4,954	$ 4,358	$ 4,104	$ 4,664	$ 4,654	$ 4,029	$ 3,674	$ 17,486		$ 17,021		$ 15,136
Operating expenses									12,854		12,637		11,895
Interest expense									1,211		1,261		1,121
Interest income									86		80		78
Depreciation and amortization									2,831		2,551		2,163
Equity in losses (earnings) of equity method investees									107		93		25
Income tax expense (benefit)									1,228		1,176		777
Income (loss) from continuing operations									2,762		2,469		1,677
Gain from discontinued operations, net of income taxes									0		0		231
Net income (loss) attributable to parent	507	879	716	650	884	660	492	430	2,752		2,465		1,908
Capital expenditures, independent power and other investments and nuclear fuel purchases									8,377		7,017		6,682
Property, plant and equipment	80,330				73,639				80,330		73,639		69,448
Accumulated depreciation and amortization	18,944				17,934				18,944		17,934		16,728
Total assets	82,479				74,605				82,479		74,605		69,007
Investment in equity method investees	1,063				663				1,063		663		422
NEER [Member]
Segment Reporting Information [Line Items]
Operating revenues									5,444		5,196		4,333
Operating expenses									3,865		3,727		3,730
Interest expense									625		667		528
Interest income									28		26		19
Depreciation and amortization									1,183		1,051		949
Equity in losses (earnings) of equity method investees									103		95		26
Income tax expense (benefit)									289		283		(42)
Income (loss) from continuing operations									1,102		993		340
Gain from discontinued operations, net of income taxes									0		0		216
Net income (loss) attributable to parent									1,092		989		556
Capital expenditures, independent power and other investments and nuclear fuel purchases									4,661		3,701		3,613
Property, plant and equipment	33,340				30,178				33,340		30,178		28,081
Accumulated depreciation and amortization	6,640				6,268				6,640		6,268		5,455
Total assets	37,647				32,896				37,647		32,896		30,052
Investment in equity method investees	983				617				983		617		388
FPL [Member]
Segment Reporting Information [Line Items]
Operating expenses									8,674		8,593		7,906
Interest expense									445		439		415
Interest income									7		3		6
Equity in losses (earnings) of equity method investees									0		0		0
Income (loss) from continuing operations									1,648		1,517		1,349
Gain from discontinued operations, net of income taxes									0		0		0
Net income (loss) attributable to parent									1,648		1,517		1,349
Capital expenditures, independent power and other investments and nuclear fuel purchases									3,633		3,241		2,903
Property, plant and equipment	45,383				41,938				45,383		41,938		39,896
Accumulated depreciation and amortization - FPL	11,862				11,282				11,862		11,282		10,944
Total assets	42,523				39,222				42,523		39,222		36,420
Investment in equity method investees	0				0				0		0		0
Corporate and Other [Member]
Segment Reporting Information [Line Items]
Operating revenues									391		404		358
Operating expenses									315		317		259
Interest expense									141		155		178
Interest income									51		51		53
Depreciation and amortization									72		68		55
Equity in losses (earnings) of equity method investees									4		(2)		(1)
Income tax expense (benefit)									(18)		(17)		(16)
Income (loss) from continuing operations									12		(41)		(12)
Gain from discontinued operations, net of income taxes									0		0		15
Net income (loss) attributable to parent									12		(41)		3
Capital expenditures, independent power and other investments and nuclear fuel purchases									83		75		166
Property, plant and equipment	1,607				1,523				1,607		1,523		1,471
Accumulated depreciation and amortization	442				384				442		384		329
Total assets	2,309				2,487				2,309		2,487		2,535
Investment in equity method investees	80				46				80		46		34
FPL [Member]
Segment Reporting Information [Line Items]
Operating revenues	2,839	3,274	2,996	2,541	2,682	3,315	2,889	2,535	11,651		11,421		10,445
Operating expenses									8,674		8,593		7,906
Interest expense									445		439		415
Depreciation and amortization									1,576		1,432		1,159
Income tax expense (benefit)									957		910		835
Net income (loss) attributable to parent	365	$ 489	$ 435	$ 359	286	$ 462	$ 423	$ 347	1,648	[1]	1,517	[1]	$ 1,349	[1]
Accumulated depreciation and amortization - FPL	11,862				11,282				11,862		11,282
Total assets	$ 42,523				$ 39,222				$ 42,523		$ 39,222

[1] FPL's comprehensive income is the same as reported net income