Employee Retirement Benefits (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Pension Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Service cost	$ 16	$ 16	$ 33	$ 32
Interest cost	25	25	49	49
Expected return on plan assets	(60)	(60)	(119)	(119)
Amortization of transition obligation	0	0	0	0
Amortization of prior service cost (benefit)	1	(1)	2	(1)
Net periodic benefit (income) cost	(18)	(20)	(35)	(39)
Other Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Service cost	1	2	3	3
Interest cost	5	5	9	11
Expected return on plan assets	0	(1)	(1)	(1)
Amortization of transition obligation	1	1	1	1
Amortization of prior service cost (benefit)	0	0	1	0
Net periodic benefit (income) cost	7	7	13	14
FPL [Member] | Pension Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Net periodic benefit (income) cost	(11)	(13)	(23)	(26)
FPL [Member] | Other Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Net periodic benefit (income) cost	$ 5	$ 5	$ 10	$ 10