Income Taxes (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Federal:
Current	$ (4)	[1]	$ (35)	[1]	$ 11	[1]
Deferred	636		572		434
Total federal	632		537		445
State:
Current	14	[1]	11	[1]	11	[1]
Deferred	46		(19)		76
Total state	60		(8)		87
Total income taxes	692		529		532
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Statutory federal income tax rate (in hundredths)	35.00%		35.00%		35.00%
Increases (reductions) resulting from:
State income taxes - net of federal income tax benefit (in hundredths)	1.50%		(0.20%)		2.40%
PTCs and ITCs - NEER (in hundredths)	(7.80%)		(11.10%)		(12.20%)
Convertible ITCs - NEER (in hundredths)	(1.50%)		(0.10%)		(2.50%)
Other - net (in hundredths)	(0.60%)		(2.00%)		(1.30%)
Effective income tax rate (in hundredths)	26.60%		21.60%		21.40%
Deferred tax liabilities:
Property-related	10,206		8,727
Pension	403		394
Storm reserve deficiency	212		235
Nuclear decommissioning trusts	115		117
Net unrealized gains on derivatives	245		209
Deferred fuel costs	0		40
Other	563		573
Total deferred tax liabilities	11,744		10,295
Deferred tax assets and valuation allowance:
Decommissioning reserves	418		406
Postretirement benefits	162		170
Net operating loss carryforwards	1,216		557
Tax credit carryforwards	2,312		2,111
ARO and accrued asset removal costs	832		884
Other	790		830
Valuation allowance	(192)	[2]	(228)	[2]
Net deferred tax assets	5,538		4,730
Net accumulated deferred income taxes	6,206		5,565
Deferred tax assets and liabilities included in the consolidated balance sheets [Abstract]
Other current assets	397	[3]	10
Other assets	113		153
Other current liabilities	(13)		(47)
Accumulated deferred income taxes	(6,703)		(5,681)
Net accumulated deferred income taxes	6,206		5,565
FPL [Member]
Federal:
Current	(261)	[1]	(64)	[1]	113	[1]
Deferred	906		622		385
Total federal	645		558		498
State:
Current	26	[1]	43	[1]	49	[1]
Deferred	81		53		33
Total state	107		96		82
Total income taxes	752		654		580
Effective Income Tax Rate, Continuing Operations, Tax Rate Reconciliation [Abstract]
Statutory federal income tax rate (in hundredths)	35.00%		35.00%		35.00%
Increases (reductions) resulting from:
State income taxes - net of federal income tax benefit (in hundredths)	3.50%		3.60%		3.50%
PTCs and ITCs - NEER (in hundredths)	0.00%		0.00%		0.00%
Convertible ITCs - NEER (in hundredths)	0.00%		0.00%		0.00%
Other - net (in hundredths)	(0.70%)		(0.60%)		(0.50%)
Effective income tax rate (in hundredths)	37.80%		38.00%		38.00%
Deferred tax liabilities:
Property-related	6,193		5,260
Pension	438		420
Storm reserve deficiency	212		235
Nuclear decommissioning trusts	0		0
Net unrealized gains on derivatives	0		0
Deferred fuel costs	0		40
Other	162		151
Total deferred tax liabilities	7,005		6,106
Deferred tax assets and valuation allowance:
Decommissioning reserves	348		336
Postretirement benefits	114		118
Net operating loss carryforwards	6		0
Tax credit carryforwards	0		0
ARO and accrued asset removal costs	723		788
Other	197		261
Valuation allowance	0	[2]	0	[2]
Net deferred tax assets	1,388		1,503
Net accumulated deferred income taxes	5,617		4,603
Deferred tax assets and liabilities included in the consolidated balance sheets [Abstract]
Other current assets	0		0
Other assets	0		0
Other current liabilities	(33)		(10)
Accumulated deferred income taxes	(5,584)		(4,593)
Net accumulated deferred income taxes	$ 5,617		$ 4,603

[1] Includes provision for unrecognized tax benefits.

[2] Amount relates to deferred state tax credits and state operating loss carryforwards.

[3] NEE expects to reclassify approximately $430 million of federal operating loss carryforwards from current deferred income taxes to noncurrent deferred income taxes in the first quarter of 2013 as a result of increased tax depreciation deductions available under the American Taxpayer Relief Act of 2012, which was enacted in January 2013.