Debt (Narrative) (Details) $ / shares in Units, € in Millions			1 Months Ended			3 Months Ended	12 Months Ended
	Sep. 01, 2016 USD ($) shares	Jun. 01, 2015 USD ($) shares	Aug. 31, 2016 USD ($) $ / shares shares	Sep. 30, 2015 USD ($) $ / shares shares	Nov. 30, 2013 shares	Sep. 30, 2016 USD ($) shares	Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 shares	Feb. 28, 2017 USD ($)	Feb. 23, 2017 USD ($)	Dec. 31, 2016 EUR (€)	Aug. 31, 2015 USD ($)	May 31, 2015 USD ($)
Debt Instrument [Line Items]
Weighted-average interest rate of commercial paper and short-tem borrowings (in hundredths)							1.07%	2.10%				1.07%
Issuances of common stock, net of issuance cost (in shares) | shares					4,500,000
FPL [Member]
Debt Instrument [Line Items]
Weighted-average interest rate of commercial paper and short-tem borrowings (in hundredths)							1.07%	0.83%				1.07%
NEER [Member]
Debt Instrument [Line Items]
Amount of debt outstanding under financing agreements related to Spain solar projects							$ 498,000,000
amount of noncurrent derivative liability related to spain solar projects							$ 122,000,000
NEE Equity Units 2012 [Member]
Debt Instrument [Line Items]
Debentures remarketed													$ 650,000,000	$ 600,000,000
Rate of interest on debentures after remarketing													2.056%	1.586%
Issuances of common stock, net of issuance cost (in shares) | shares		7,860,000				8,173,099
Issuances of common stock		$ 600,000,000				$ 650,000,000
NEE Equity Units 2015 [Member]
Sale of equity units [Abstract]
Amount of equity units sold				$ 700,000,000
Stated amount of each equity unit (in dollars per share) | $ / shares				$ 50
Undivided beneficial ownership interest per debenture (in hundredths)				5.00%
Principal amount of each debenture				$ 1,000
Price per share of stock purchase contract - low range (in dollars per share) | $ / shares				$ 95.35
Price per share of stock purchase contract - high range (in dollars per share) | $ / shares				$ 114.42
Number of shares (subject to antidilution adjustments) if purchased on final settlement date at less than or equal to low range threshold (in shares) | shares				0.5261
Number of shares (subject to antidilution adjustments) if purchased on the final settlement date at equal to or greater than high range threshold (in shares) | shares				0.4385
Trading period (in days) over which the market value is determined by reference to the average closing prices of the common stock				20 days
Rate of total annual distributions on equity units (in hundredths)				6.371%
Interest rate				2.36%
Rate of payments on stock purchase contracts (in hundredths)				4.011%
NEE Equity Units 2016 [Member]
Sale of equity units [Abstract]
Amount of equity units sold			$ 1,500,000,000
Stated amount of each equity unit (in dollars per share) | $ / shares			$ 50
Undivided beneficial ownership interest per debenture (in hundredths)			5.00%
Principal amount of each debenture			$ 1,000
Number of shares (subject to antidilution adjustments) if purchased on final settlement date at less than or equal to low range threshold (in shares) | shares			0.3918
Number of shares (subject to antidilution adjustments) if purchased on the final settlement date at equal to or greater than high range threshold (in shares) | shares			0.3134
Trading period (in days) over which the market value is determined by reference to the average closing prices of the common stock			20 days
Rate of total annual distributions on equity units (in hundredths)			6.123%
Interest rate			1.65%
Rate of payments on stock purchase contracts (in hundredths)			4.473%
September 2013 Equity Units [Member]
Debt Instrument [Line Items]
Debentures remarketed						$ 500,000,000
Rate of interest on debentures after remarketing						1.649%
Minimum [Member] | NEE Equity Units 2016 [Member]
Sale of equity units [Abstract]
Price Per Share of Stock Purchase Contract | $ / shares			$ 127.63
Maximum [Member] | NEE Equity Units 2016 [Member]
Sale of equity units [Abstract]
Price Per Share of Stock Purchase Contract | $ / shares			$ 159.54
Common Stock [Member]
Debt Instrument [Line Items]
Issuances of common stock, net of issuance cost (in shares) | shares							6,000,000	17,000,000	7,000,000
Issuances of common stock								$ 1,000,000
Common Stock [Member] | September 2013 Equity Units [Member]
Debt Instrument [Line Items]
Issuances of common stock, net of issuance cost (in shares) | shares	5,101,000
Issuances of common stock	$ 500,000,000
Standby Letters of Credit [Member] | Capital Holdings [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity							$ 26,000,000					€ 23
Line of Credit [Member]
Debt Instrument [Line Items]
Available capacity							10,200,000,000
Line of Credit [Member] | FPL [Member]
Debt Instrument [Line Items]
Available capacity							3,600,000,000
Revolving Credit Facility [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Available capacity							9,800,000,000
Revolving Credit Facility [Member] | Line of Credit [Member] | FPL [Member]
Debt Instrument [Line Items]
Available capacity							3,600,000,000
Revolving Credit Facility, Issuance of Letters of Credit [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Available capacity							3,400,000,000
Revolving Credit Facility, Issuance of Letters of Credit [Member] | Line of Credit [Member] | FPL [Member]
Debt Instrument [Line Items]
Available capacity							700,000,000
Letter of Credit [Member] | Line of Credit [Member]
Debt Instrument [Line Items]
Available capacity							400,000,000
Letter of Credit [Member] | Line of Credit [Member] | FPL [Member]
Debt Instrument [Line Items]
Available capacity							$ 0
Subsequent Event [Member] | Short-Term, Non-Revolving Term Loan Facility [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity											$ 7,500,000,000.0
Subsequent Event [Member] | Short-Term, Non-Revolving Term Loan Facility 1 [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity											$ 3,750,000,000.00
Subsequent Event [Member] | Short-Term, Non-Revolving Term Loan Facility 2 [Member] | Term Loan [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity										$ 3,750,000,000.00