Summary of Significant Accounting and Reporting Policies (Goodwill and Intangible Assets) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill and Intangible Assets [Line Items]
Goodwill	$ 778	$ 147
Other intangible assets not subject to amortization, primarily land easements	143	143
Other intangible assets:
Total	1,184	487
Accumulated amortization	(120)	(125)
Total other intangible assets subject to amortization - net	1,064	362
Intangible assets, amortization [Abstract]
NextEra Energy Resources' amortization expense	17	15	$ 13
Amortization Expense 2016	38
Amortization Expense 2017	37
Amortization Expense 2018	36
Amortization Expense 2019	35
Amortization Expense 2020	$ 35
Customer relationships associated with gas infrastructure
Other intangible assets:
Weighted average useful lives (years)	40 years
Total	$ 720	0
Purchased power agreements
Other intangible assets:
Weighted average useful lives (years)	22 years
Total	$ 328	348
Other, primarily transmission and development rights
Other intangible assets:
Weighted average useful lives (years)	22 years
Total	$ 136	139
Gas Infrastructure [Member]
Goodwill and Intangible Assets [Line Items]
Goodwill	635	0
Customer Supply [Member]
Goodwill and Intangible Assets [Line Items]
Goodwill	72	72
Generation Assets Unit Member [Member]
Goodwill and Intangible Assets [Line Items]
Goodwill	43	47
Other Goodwill Assets [Member]
Goodwill and Intangible Assets [Line Items]
Goodwill	$ 28	$ 28