Summary of Significant Accounting and Reporting Policies (Regulatory Assets and Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Current:
Acquisition of purchased power agreements	$ 165	$ 165
Deferred clause and franchise expenses	146	10
Other	137	161
Total	448	336	[1]
Noncurrent:
Purchased power agreement termination	798	963
Other	2,492	1,506
Total	3,290	2,469	[1]
Current:
Deferred clause revenues	265	296
Other	60	50
Total	325	346	[1]
Noncurrent:
Asset retirement obligation regulatory expense difference	2,352	2,569
Deferred Tax Liabilities, Net, Noncurrent	4,815	4,981
Other	1,842	1,215
Total	9,009	8,765	[1]
FPL[Member]
Current:
Acquisition of purchased power agreements	165	165
Deferred clause and franchise expenses	146	10
Other	136	160
Total	447	335	[2]
Noncurrent:
Purchased power agreement termination	798	963
Other	2,045	1,286
Total	2,843	2,249	[2]
Current:
Deferred clause revenues	265	296
Other	45	37
Total	310	333	[2]
Noncurrent:
Asset retirement obligation regulatory expense difference	2,352	2,569
Deferred Tax Liabilities, Net, Noncurrent	4,736	4,903
Other	1,798	1,170
Total	$ 8,886	$ 8,642	[2]

[1] Amounts have been retrospectively adjusted as discussed in Note 14.

[2] Amounts have been retrospectively adjusted as discussed in Note 14.