Employee Retirement Benefits (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Pension Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Service cost	$ 19	$ 16	$ 55	$ 49
Interest cost	23	25	71	74
Expected return on plan assets	(59)	(60)	(178)	(179)
Amortization of transition obligation	0	0	0	0
Amortization of prior service cost (benefit)	2	1	6	3
Amortization of losses	0	0	1	0
Special termination benefits	15	0	27	0
Net periodic benefit (income) cost	0	(18)	(18)	(53)
Other Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Service cost	1	1	3	4
Interest cost	3	4	11	13
Expected return on plan assets	(1)	0	(1)	(1)
Amortization of transition obligation	0	0	0	1
Amortization of prior service cost (benefit)	0	(1)	(2)	0
Amortization of losses	1	0	2	0
Special termination benefits	0	0	0	0
Net periodic benefit (income) cost	4	4	13	17
FPL [Member] | Pension Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Net periodic benefit (income) cost	2	(11)	(10)	(34)
FPL [Member] | Other Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Net periodic benefit (income) cost	$ 3	$ 3	$ 9	$ 13