Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Deferred tax liabilities:
Property-related	$ 10,133	$ 9,315
Pension	417	374
Investments in partnerships and joint ventures	2,019	1,925
Other	1,618	1,505
Total deferred tax liabilities	14,187	13,119
Deferred tax assets and valuation allowance:
Decommissioning reserves	317	313
Net operating loss carryforwards	380	350
Tax credit carryforwards	3,406	3,259
ARO and accrued asset removal costs	368	310
Regulatory liabilities	1,335	1,277
Other	515	751
Valuation allowance	(285)	(273)
Net deferred tax assets	6,036	5,987
Net deferred income taxes	8,151	7,132
Deferred tax assets and liabilities included in the consolidated balance sheets [Abstract]
Noncurrent other assets	210	235
Deferred income taxes - noncurrent liabilities	(8,361)	(7,367)
Net deferred income taxes	(8,151)	(7,132)
FPL[Member]
Deferred tax liabilities:
Property-related	6,394	6,113
Pension	374	357
Investments in partnerships and joint ventures	0	0
Other	685	791
Total deferred tax liabilities	7,453	7,261
Deferred tax assets and valuation allowance:
Decommissioning reserves	286	278
Net operating loss carryforwards	2	3
Tax credit carryforwards	0	0
ARO and accrued asset removal costs	273	237
Regulatory liabilities	1,219	1,283
Other	258	295
Valuation allowance	0	0
Net deferred tax assets	2,038	2,096
Net deferred income taxes	5,415	5,165
Deferred tax assets and liabilities included in the consolidated balance sheets [Abstract]
Noncurrent other assets	0	0
Deferred income taxes - noncurrent liabilities	(5,415)	(5,165)
Net deferred income taxes	$ (5,415)	$ (5,165)