Income Taxes (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016 USD ($) MW	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($) MW	Jun. 30, 2015 USD ($)
Income Tax Contingency [Line Items]
Effective income tax rate (as a percent)	29.00%	28.00%	28.00%	29.00%
Production tax credits	$ 31	$ 37	$ 73	$ 75
Deferred income tax benefit associated with convertible investment tax credits	43	$ 34	79	$ 52
Income tax benefits associated with the reorganization of certain Canadian assets	30		30
NextEra Energy Resources subsidiary [Member] | Merchant Natural Gas Generation Facilities [Member]
Income Tax Contingency [Line Items]
Income tax charge associated with the sale of ownership interest	$ 58		$ 58
Total generating capacity | MW	2,884		2,884