Fair Value Measurements (Assets and Liabilities Measured on a Recurring Basis) (Details) (Fair value measurements made on a recurring basis [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Cash equivalents:
Equity securities	$ 84		$ 20
Special use funds:
Equity securities	2,525	[1]	2,506	[1]
U.S. Government and municipal bonds	783	[1]	827	[1]
Corporate debt securities	612	[1]	597	[1]
Mortgage-backed securities	514	[1]	479	[1]
Other debt securities	69	[1]	60	[1]
Fair value of investments in commingled funds whose underlying investments would be Level 1 if those investments were held directly by the registrant			1,300
Other investments:
Equity Securities	44		51
Debt securities	124		118
Derivatives:
Commodity contracts	1,441	[2]	1,571	[2]
Interest rate contracts	76	[2]	90	[2]
Derivatives:
Commodity contracts	834	[2]	940	[2]
Interest rate swaps	233	[2]	220	[2]
Foreign currency swaps	144	[2]	151	[2]
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member]
Cash equivalents:
Equity securities	84		20
Special use funds:
Equity securities	1,235	[1]	1,170	[1]
U.S. Government and municipal bonds	617	[1]	647	[1]
Corporate debt securities	0	[1]	0	[1]
Mortgage-backed securities	0	[1]	0	[1]
Other debt securities	25	[1]	16	[1]
Other investments:
Equity Securities	44		51
Debt securities	21		11
Derivatives:
Commodity contracts	1,529		1,368
Interest rate contracts	0		0
Derivatives:
Commodity contracts	1,434		1,285
Interest rate swaps	0		0
Foreign currency swaps	0		0
Significant Other Observable Inputs (Level 2) [Member]
Cash equivalents:
Equity securities	0		0
Special use funds:
Equity securities	1,290	[1],[3]	1,336	[1],[4]
U.S. Government and municipal bonds	166	[1]	180	[1]
Corporate debt securities	612	[1]	597	[1]
Mortgage-backed securities	514	[1]	479	[1]
Other debt securities	44	[1]	44	[1]
Other investments:
Equity Securities	0		0
Debt securities	103		107
Derivatives:
Commodity contracts	1,989		2,106
Interest rate contracts	76		90
Derivatives:
Commodity contracts	1,804		1,994
Interest rate swaps	125		127
Foreign currency swaps	144		151
Significant Unobservable Inputs (Level 3) [Member]
Cash equivalents:
Equity securities	0		0
Special use funds:
Equity securities	0	[1]	0	[1]
U.S. Government and municipal bonds	0	[1]	0	[1]
Corporate debt securities	0	[1]	0	[1]
Mortgage-backed securities	0	[1]	0	[1]
Other debt securities	0	[1]	0	[1]
Other investments:
Equity Securities	0		0
Debt securities	0		0
Derivatives:
Commodity contracts	1,035		1,069
Interest rate contracts	0		0
Derivatives:
Commodity contracts	467		354
Interest rate swaps	108		93
Foreign currency swaps	0		0
Netting [Member]
Cash equivalents:
Equity securities	0	[5]	0	[5]
Special use funds:
Equity securities	0	[1],[5]	0	[1],[5]
U.S. Government and municipal bonds	0	[1],[5]	0	[1],[5]
Corporate debt securities	0	[1],[5]	0	[1],[5]
Mortgage-backed securities	0	[1],[5]	0	[1],[5]
Other debt securities	0	[1],[5]	0	[1],[5]
Other investments:
Equity Securities	0	[5]	0	[5]
Debt securities	0	[5]	0	[5]
Derivatives:
Commodity contracts	(3,112)	[5]	(2,972)	[5]
Interest rate contracts	0	[5]	0	[5]
Derivatives:
Commodity contracts	(2,871)	[5]	(2,693)	[5]
Interest rate swaps	0	[5]	0	[5]
Foreign currency swaps	0	[5]	0	[5]
FPL [Member]
Special use funds:
Equity securities	1,494	[1]	1,467	[1]
U.S. Government and municipal bonds	667	[1]	738	[1]
Corporate debt securities	427	[1]	421	[1]
Mortgage-backed securities	438	[1]	401	[1]
Other debt securities	50	[1]	46	[1]
Fair value of investments in commingled funds whose underlying investments would be Level 1 if those investments were held directly by the registrant			1,141
Derivatives:
Commodity contracts	130	[2]	48	[2]
Derivatives:
Commodity contracts	10	[2]	2	[2]
FPL [Member] | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member]
Special use funds:
Equity securities	366	[1]	291	[1]
U.S. Government and municipal bonds	520	[1]	584	[1]
Corporate debt securities	0	[1]	0	[1]
Mortgage-backed securities	0	[1]	0	[1]
Other debt securities	25	[1]	16	[1]
Derivatives:
Commodity contracts	0		0
Derivatives:
Commodity contracts	0		0
FPL [Member] | Significant Other Observable Inputs (Level 2) [Member]
Special use funds:
Equity securities	1,128	[1],[3]	1,176	[1],[4]
U.S. Government and municipal bonds	147	[1]	154	[1]
Corporate debt securities	427	[1]	421	[1]
Mortgage-backed securities	438	[1]	401	[1]
Other debt securities	25	[1]	30	[1]
Derivatives:
Commodity contracts	119		53
Derivatives:
Commodity contracts	2		7
FPL [Member] | Significant Unobservable Inputs (Level 3) [Member]
Special use funds:
Equity securities	0	[1]	0	[1]
U.S. Government and municipal bonds	0	[1]	0	[1]
Corporate debt securities	0	[1]	0	[1]
Mortgage-backed securities	0	[1]	0	[1]
Other debt securities	0	[1]	0	[1]
Derivatives:
Commodity contracts	4		2
Derivatives:
Commodity contracts	1		2
FPL [Member] | Netting [Member]
Special use funds:
Equity securities	0	[1],[5]	0	[1],[5]
U.S. Government and municipal bonds	0	[1],[5]	0	[1],[5]
Corporate debt securities	0	[1],[5]	0	[1],[5]
Mortgage-backed securities	0	[1],[5]	0	[1],[5]
Other debt securities	0	[1],[5]	0	[1],[5]
Derivatives:
Commodity contracts	7	[5]	(7)	[5]
Derivatives:
Commodity contracts	$ 7	[5]	$ (7)	[5]

[1] Excludes investments accounted for under the equity method and loans not measured at fair value on a recurring basis. See Fair Value of Financial Instruments Recorded at the Carrying Amount below.

[2] See Note 2 - Fair Value of Derivative Instruments for a reconciliation of net derivatives to NEE's and FPL's condensed consolidated balance sheets.

[3] Invested in commingled funds whose underlying securities would be Level 1 if those securities were held directly by NEE or FPL.

[4] At NEE, approximately $1,300 million ($1,141 million at FPL) are invested in commingled funds whose underlying securities would be Level 1 if those securities were held directly by NEE or FPL.

[5] Includes the effect of the contractual ability to settle contracts under master netting arrangements and margin cash collateral payments and receipts. NEE and FPL also have contract settlement receivable and payable balances that are subject to the master netting arrangements but are not offset within the condensed consolidated balance sheets and are recorded in customer receivables - net and accounts payable, respectively.