Fair Value Measurements (Details) (Fair value measurements made on a recurring basis [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2012		Dec. 31, 2011
Cash equivalents:
Equity securities	$ 22		$ 159
Special use funds:
Equity securities	2,106		1,915
U.S. Government and municipal bonds	664		675
Corporate debt securities	549		516
Mortgage-backed securities	594		511
Other debt securities	47		47
Other investments:
Equity securities	12		4
U.S. Government and municipal bonds	11		8
Corporate debt securities	52		43
Mortgage-backed securities	47		33
Other	10		10
Derivatives:
Commodity contracts	1,331	[1]	1,520	[1]
Interest rate swaps	80	[1]	37	[1]
Foreign currency swaps	15	[1]	27	[1]
Derivatives:
Commodity contracts	615	[1]	1,302	[1]
Interest rate swaps	391	[1]	320	[1]
Foreign currency swaps	10	[1]	9	[1]
Fair value of investments in commingled funds whose underlying investments would be Level 1 if those investments were held directly by the registrant	1,217		1,086
FPL [Member]
Cash equivalents:
Equity securities	1		11
Special use funds:
Equity securities	1,292		1,184
U.S. Government and municipal bonds	574		592
Corporate debt securities	381		359
Mortgage-backed securities	513		434
Other debt securities	35		32
Derivatives:
Commodity contracts	40	[1]	12	[1]
Derivatives:
Commodity contracts	67	[1]	513	[1]
Fair value of investments in commingled funds whose underlying investments would be Level 1 if those investments were held directly by the registrant	1,093		979
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member]
Cash equivalents:
Equity securities	22		159
Special use funds:
Equity securities	813		709
U.S. Government and municipal bonds	495		508
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other debt securities	0		0
Other investments:
Equity securities	12		4
U.S. Government and municipal bonds	11		8
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other	5		5
Derivatives:
Commodity contracts	1,407		2,448
Interest rate swaps	0		0
Foreign currency swaps	0		0
Derivatives:
Commodity contracts	1,461		2,588
Interest rate swaps	0		0
Foreign currency swaps	0		0
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member] | FPL [Member]
Cash equivalents:
Equity securities	1		11
Special use funds:
Equity securities	150		128
U.S. Government and municipal bonds	442		458
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other debt securities	0		0
Derivatives:
Commodity contracts	0		0
Derivatives:
Commodity contracts	0		0
Significant Other Observable Inputs (Level 2) [Member]
Cash equivalents:
Equity securities	0		0
Special use funds:
Equity securities	1,293	[2]	1,206	[3]
U.S. Government and municipal bonds	169		167
Corporate debt securities	549		516
Mortgage-backed securities	594		511
Other debt securities	47		47
Other investments:
Equity securities	0		0
U.S. Government and municipal bonds	0		0
Corporate debt securities	52		43
Mortgage-backed securities	47		33
Other	5		5
Derivatives:
Commodity contracts	2,605		3,478
Interest rate swaps	80		37
Foreign currency swaps	15		27
Derivatives:
Commodity contracts	2,197		3,582
Interest rate swaps	391		320
Foreign currency swaps	10		9
Significant Other Observable Inputs (Level 2) [Member] | FPL [Member]
Cash equivalents:
Equity securities	0		0
Special use funds:
Equity securities	1,142	[2]	1,056	[2]
U.S. Government and municipal bonds	132		134
Corporate debt securities	381		359
Mortgage-backed securities	513		434
Other debt securities	35		32
Derivatives:
Commodity contracts	82		8
Derivatives:
Commodity contracts	114		513
Significant Unobservable Inputs (Level 3) [Member]
Cash equivalents:
Equity securities	0		0
Special use funds:
Equity securities	0		0
U.S. Government and municipal bonds	0		0
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other debt securities	0		0
Other investments:
Equity securities	0		0
U.S. Government and municipal bonds	0		0
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other	0		0
Derivatives:
Commodity contracts	831		1,071
Interest rate swaps	0		0
Foreign currency swaps	0		0
Derivatives:
Commodity contracts	349		585
Interest rate swaps	0		0
Foreign currency swaps	0		0
Significant Unobservable Inputs (Level 3) [Member] | FPL [Member]
Cash equivalents:
Equity securities	0		0
Special use funds:
Equity securities	0		0
U.S. Government and municipal bonds	0		0
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other debt securities	0		0
Derivatives:
Commodity contracts	5		6
Derivatives:
Commodity contracts	0		2
Netting [Member]
Cash equivalents:
Equity securities	0	[4]	0	[4]
Special use funds:
Equity securities	0	[4]	0	[4]
U.S. Government and municipal bonds	0	[4]	0	[4]
Corporate debt securities	0	[4]	0	[4]
Mortgage-backed securities	0	[4]	0	[4]
Other debt securities	0	[4]	0	[4]
Other investments:
Equity securities	0	[4]	0	[4]
U.S. Government and municipal bonds	0	[4]	0	[4]
Corporate debt securities	0	[4]	0	[4]
Mortgage-backed securities	0	[4]	0	[4]
Other	0	[4]	0	[4]
Derivatives:
Commodity contracts	(3,512)	[4]	(5,477)	[4]
Interest rate swaps	0	[4]	0	[4]
Foreign currency swaps	0	[4]	0	[4]
Derivatives:
Commodity contracts	(3,392)	[4]	(5,453)	[4]
Interest rate swaps	0	[4]	0	[4]
Foreign currency swaps	0	[4]	0	[4]
Netting [Member] | FPL [Member]
Cash equivalents:
Equity securities	0	[4]	0	[4]
Special use funds:
Equity securities	0	[4]	0	[4]
U.S. Government and municipal bonds	0	[4]	0	[4]
Corporate debt securities	0	[4]	0	[4]
Mortgage-backed securities	0	[4]	0	[4]
Other debt securities	0	[4]	0	[4]
Derivatives:
Commodity contracts	(47)	[4]	(2)	[4]
Derivatives:
Commodity contracts	$ (47)	[4]	$ (2)	[4]

[1] See Note 2 for a reconciliation of net derivatives to NEE's and FPL's condensed consolidated balance sheets.

[2] At NEE, approximately $1,217 million ($1,093 million at FPL) are invested in commingled funds whose underlying investments would be Level 1 if those investments were held directly by NEE or FPL.

[3] At NEE, approximately $1,086 million ($979 million at FPL) are invested in commingled funds whose underlying investments would be Level 1 if those investments were held directly by NEE or FPL.

[4] Includes the effect of the contractual ability to settle contracts under master netting arrangements and margin cash collateral payments and receipts.