Fair Value Measurements (Details) (Fair value measurements made on a recurring basis [Member], USD $) In Millions, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Cash equivalents:
Equity securities	$ 109		$ 23
Special use funds:
Equity securities	2,516		2,154
U.S. Government and municipal bonds	647		594
Corporate debt securities	560		572
Mortgage-backed securities	510		560
Other debt securities	61		41
Other investments:
Equity securities	45		7
U.S. Government and municipal bonds	21		6
Corporate debt securities	56		53
Mortgage-backed securities	38		47
Other	10		11
Derivatives:
Commodity contracts	1,374	[1]	1,361	[1]
Interest rate contracts	78	[1]	76	[1]
Derivatives:
Commodity contracts	631	[1]	564	[1]
Interest rate swaps	221	[1]	387	[1]
Foreign currency swaps	117	[1]	66	[1]
Fair value of investments in commingled funds whose underlying investments would be Level 1 if those investments were held directly by the registrant	1,461		1,214
FPL [Member]
Cash equivalents:
Equity securities	4		5
Special use funds:
Equity securities	1,547		1,335
U.S. Government and municipal bonds	560		509
Corporate debt securities	397		397
Mortgage-backed securities	429		475
Other debt securities	46		32
Derivatives:
Commodity contracts	2	[1]	5	[1]
Derivatives:
Commodity contracts	63	[1]	20	[1]
Fair value of investments in commingled funds whose underlying investments would be Level 1 if those investments were held directly by the registrant	1,317		1,093
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member]
Cash equivalents:
Equity securities	109		23
Special use funds:
Equity securities	1,041		914
U.S. Government and municipal bonds	491		451
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other debt securities	19		15
Other investments:
Equity securities	45		7
U.S. Government and municipal bonds	11		6
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other	5		5
Derivatives:
Commodity contracts	1,054		1,187
Interest rate contracts	0		0
Derivatives:
Commodity contracts	1,027		1,240
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	4		5
Special use funds:
Equity securities	217		217
U.S. Government and municipal bonds	429		390
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other debt securities	18		16
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	1,475	[2]	1,240	[3]
U.S. Government and municipal bonds	156		143
Corporate debt securities	560		572
Mortgage-backed securities	510		560
Other debt securities	42		26
Other investments:
Equity securities	0		0
U.S. Government and municipal bonds	10		0
Corporate debt securities	56		53
Mortgage-backed securities	38		47
Other	5		6
Derivatives:
Commodity contracts	1,844		2,251
Interest rate contracts	78		76
Derivatives:
Commodity contracts	1,665		1,844
Interest rate swaps	130		387
Foreign currency swaps	117		66
Significant Other Observable Inputs (Level 2) [Member] | FPL [Member]
Cash equivalents:
Equity securities	0		0
Special use funds:
Equity securities	1,330	[2]	1,118	[2]
U.S. Government and municipal bonds	131		119
Corporate debt securities	397		397
Mortgage-backed securities	429		475
Other debt securities	28		16
Derivatives:
Commodity contracts	7		14
Derivatives:
Commodity contracts	69		31
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	937		794
Interest rate contracts	0		0
Derivatives:
Commodity contracts	222		228
Interest rate swaps	91		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	2		3
Derivatives:
Commodity contracts	1		1
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	(2,461)	[4]	(2,871)	[4]
Interest rate contracts	0	[4]	0	[4]
Derivatives:
Commodity contracts	(2,283)	[4]	(2,748)	[4]
Interest rate swaps	0	[4]	0	[4]
Foreign currency swaps	0	[4]	0	[4]
Netting [Member] | FPL [Member]
Cash equivalents:
Equity securities	0		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	(7)	[4]	(12)	[4]
Derivatives:
Commodity contracts	$ (7)	[4]	$ (12)	[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 $1,461 million ($1,317 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 $1,214 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.

[4] 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.