Fair Value Measurements (Details) (Fair value measurements made on a recurring basis [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2013		Dec. 31, 2012
Cash equivalents:
Equity securities	$ 3		$ 23
Special use funds:
Equity securities	2,335		2,154
U.S. Government and municipal bonds	656		594
Corporate debt securities	576		572
Mortgage-backed securities	518		560
Other debt securities	48		41
Other investments:
Equity securities	43		7
U.S. Government and municipal bonds	5		6
Corporate debt securities	60		53
Mortgage-backed securities	45		47
Other	11		11
Derivatives:
Commodity contracts	1,315	[1]	1,361	[1]
Interest rate swaps	73	[1]	76	[1]
Derivatives:
Commodity contracts	423	[1]	564	[1]
Interest rate swaps	284	[1]	387	[1]
Foreign currency swaps	103	[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	1,350		1,214
FPL [Member]
Cash equivalents:
Equity securities			5
Special use funds:
Equity securities	1,452		1,335
U.S. Government and municipal bonds	563		509
Corporate debt securities	394		397
Mortgage-backed securities	436		475
Other debt securities	38		32
Derivatives:
Commodity contracts	145	[1]	5	[1]
Derivatives:
Commodity contracts	1	[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	1,216		1,093
Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) [Member]
Cash equivalents:
Equity securities	3		23
Special use funds:
Equity securities	965		914
U.S. Government and municipal bonds	537		451
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other debt securities	19		15
Other investments:
Equity securities	43		7
U.S. Government and municipal bonds	5		6
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other	5		5
Derivatives:
Commodity contracts	1,083		1,187
Interest rate swaps	0		0
Derivatives:
Commodity contracts	1,122		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			5
Special use funds:
Equity securities	219		217
U.S. Government and municipal bonds	456		390
Corporate debt securities	0		0
Mortgage-backed securities	0		0
Other debt securities	19		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	1,370	[2]	1,240	[3]
U.S. Government and municipal bonds	119		143
Corporate debt securities	576		572
Mortgage-backed securities	518		560
Other debt securities	29		26
Other investments:
Equity securities	0		0
U.S. Government and municipal bonds	0		0
Corporate debt securities	60		53
Mortgage-backed securities	45		47
Other	6		6
Derivatives:
Commodity contracts	2,203		2,251
Interest rate swaps	73		76
Derivatives:
Commodity contracts	1,674		1,844
Interest rate swaps	284		387
Foreign currency swaps	103		66
Significant Other Observable Inputs (Level 2) [Member] | FPL [Member]
Cash equivalents:
Equity securities			0
Special use funds:
Equity securities	1,233	[2]	1,118	[2]
U.S. Government and municipal bonds	107		119
Corporate debt securities	394		397
Mortgage-backed securities	436		475
Other debt securities	19		16
Derivatives:
Commodity contracts	142		14
Derivatives:
Commodity contracts	0		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	816		794
Interest rate swaps	0		0
Derivatives:
Commodity contracts	294		228
Interest rate swaps	0		0
Foreign currency swaps	0		0
Significant Unobservable Inputs (Level 3) [Member] | FPL [Member]
Cash equivalents:
Equity securities			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	4		3
Derivatives:
Commodity contracts	2		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	(2,787)	[4]	(2,871)	[4]
Interest rate swaps	0	[4]	0	[4]
Derivatives:
Commodity contracts	(2,667)	[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	[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	(1)	[4]	(12)	[4]
Derivatives:
Commodity contracts	$ (1)	[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 $1,350 million ($1,216 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 also has 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.