Quarterly Data (Unaudited) (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2011		Sep. 30, 2011		Jun. 30, 2011		Mar. 31, 2011		Dec. 31, 2010		Sep. 30, 2010		Jun. 30, 2010		Mar. 31, 2010		Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Condensed consolidated quarterly financial information [Abstract]
Operating revenues	$ 3,864	[1],[2]	$ 4,382	[1],[2]	$ 3,961	[1],[2]	$ 3,134	[1],[2]	$ 3,413	[1],[2]	$ 4,691	[1],[2]	$ 3,591	[1],[2]	$ 3,622	[1],[2]	$ 15,341	$ 15,317	$ 15,643
Operating income	1,132	[1],[2]	911	[1],[2]	907	[1],[2]	428	[1],[2]	469	[1],[2]	1,125	[1],[2]	709	[1],[2]	939	[1],[2]	3,378	3,243	2,594
Net income (loss)	$ 667	[1],[2]	$ 407	[1],[2]	$ 580	[1],[2]	$ 268	[1],[2]	$ 263	[1],[2]	$ 720	[1],[2]	$ 417	[1],[2]	$ 556	[1],[2]	$ 1,923	$ 1,957	$ 1,615
Earnings per share (in dollars per share)	$ 1.60	[1],[3]	$ 0.98	[1],[3]	$ 1.39	[1],[3]	$ 0.64	[1],[3]	$ 0.64	[1],[3]	$ 1.75	[1],[3]	$ 1.02	[1],[3]	$ 1.36	[1],[3]	$ 4.62	$ 4.77	$ 3.99
Earnings per share - assuming dilution (in dollars per share)	$ 1.59	[1],[3]	$ 0.97	[1],[3]	$ 1.38	[1],[3]	$ 0.64	[1],[3]	$ 0.63	[1],[3]	$ 1.74	[1],[3]	$ 1.01	[1],[3]	$ 1.36	[1],[3]	$ 4.59	$ 4.74	$ 3.97
Dividends per share (in dollars per share)	$ 0.55	[1]	$ 0.55	[1]	$ 0.55	[1]	$ 0.55	[1]	$ 0.50	[1]	$ 0.50	[1]	$ 0.50	[1]	$ 0.50	[1]	$ 2.20	$ 2.00	$ 1.89
High common stock sales price (in dollars per share)	$ 61.20	[1]	$ 58.25	[1]	$ 58.98	[1]	$ 55.86	[1]	$ 56.26	[1]	$ 55.98	[1]	$ 53.50	[1]	$ 53.75	[1]
Low common stock sales price (in dollars per share)	$ 51.33	[1]	$ 49.00	[1]	$ 54.16	[1]	$ 51.54	[1]	$ 50.00	[1]	$ 48.44	[1]	$ 47.96	[1]	$ 45.29	[1]

[1] In the opinion of NEE and FPL, all adjustments, which consist of normal recurring accruals necessary to present a fair statement of the amounts shown for such periods, have been made. Results of operations for an interim period generally will not give a true indication of results for the year.

[2] The sum of the quarterly amounts may not equal the total for the year due to rounding.

[3] The sum of the quarterly amounts may not equal the total for the year due to rounding and changes in weighted-average number of common shares outstanding.