Equity (Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018		Sep. 30, 2019	Sep. 30, 2018
Reconciliation of basic and diluted earnings per share of common stock [Abstract]
Net income (loss) attributable to NEE	$ 879	$ 1,005	[1]	$ 2,794	$ 6,216	[1]
Adjustment for the impact of dilutive securities at NEP	0	(4)		0	(33)
Net income attributable to NEE - assuming dilution	$ 879	$ 1,001		$ 2,794	$ 6,183
Denominator:
Weighted-average number of common shares outstanding - basic	481.9	473.1	[1]	479.7	471.7	[1]
Equity units, stock options, performance share awards and restricted stock	4.1	4.3		3.8	3.9
Weighted-average number of common shares outstanding - assuming dilution	486.0	477.4	[1]	483.5	475.6	[1]
Earnings per share attributable to NEE:(a)
Basic (in dollars per share)	$ 1.82	$ 2.12	[1]	$ 5.82	$ 13.18	[1]
Assuming dilution (in dollars per share)	$ 1.81	$ 2.10	[1]	$ 5.78	$ 13.00	[1]
Antidilutive securities (in shares)	2.2			1.0	0.2

[1] Amounts have been retrospectively adjusted for an accounting standards update related to leases.