Employee Retirement Benefits - Net Periodic Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Pension Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Service cost	$ 86	$ 90	$ 85
Interest cost	77	64	92
Expected return on plan assets	(363)	(339)	(321)
Amortization of actuarial loss	0	24	18
Amortization of prior service benefit	(1)	(1)	(1)
Special termination benefits	52	0	16
Benefit plan settlement	27	0	0
Net periodic (income) cost	(122)	(162)	(111)
Other Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Service cost	1	2	1
Interest cost	5	4	8
Expected return on plan assets	0	0	0
Amortization of actuarial loss	3	5	3
Amortization of prior service benefit	(4)	(15)	(16)
Special termination benefits	0	0	0
Benefit plan settlement	0	0	0
Net periodic (income) cost	5	(4)	(4)
FPL [Member] | Pension Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Net periodic (income) cost	(76)	(108)	(84)
FPL [Member] | Other Benefits [Member]
Net periodic benefit (income) cost [Abstract]
Net periodic (income) cost	$ 4	$ (4)	$ (4)