Derivative Instruments (Balance Sheet Disclosure) (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 2,006	$ 1,971
Derivative Liability	1,376	1,428
Current derivative assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	612	712
Derivative Asset, Collateral, Obligation to Return Cash, Offset	148	279
Assets held for sale [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		57
Non Current Derivative Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	1,394	1,202
Derivative Asset, Collateral, Obligation to Return Cash, Offset	93	151
Current derivative liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	377	882
Derivative Liability, Collateral, Right to Reclaim Cash, Offset		46
Liabilities associated with assets held-for-sale [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability		16
Noncurrent derivative liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	999	530
Derivative Liability, Collateral, Right to Reclaim Cash, Offset		13
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		33
Derivative Liability, Fair Value, Gross Liability		287
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	5,174	5,908
Derivative Liability, Fair Value, Gross Liability	4,302	4,740
Derivative Asset	2,006
Derivative Liability	1,376
FPL [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	33	4
Derivative Liability	5	222
FPL [Member] \| Current derivative assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	22	3
FPL [Member] \| Non Current Derivative Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	11	1
FPL [Member] \| Current derivative liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	5	222
Commodity Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		0
Derivative Liability, Fair Value, Gross Liability		0
Commodity Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	5,105	5,906
Derivative Liability, Fair Value, Gross Liability	3,479	4,580
Derivative Asset	1,943	1,937
Derivative Liability	558	982
Commodity Contract [Member] \| FPL [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		0
Derivative Liability, Fair Value, Gross Liability		0
Commodity Contract [Member] \| FPL [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	48	7
Derivative Liability, Fair Value, Gross Liability	20	225
Derivative Asset	33	4
Derivative Liability	5	222
Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		34
Derivative Liability		319
Interest Rate Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		33
Derivative Liability, Fair Value, Gross Liability		155
Interest Rate Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	60	2
Derivative Liability, Fair Value, Gross Liability	788	160
Derivative Asset	55
Derivative Liability	782
Foreign Exchange Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		0
Derivative Liability		127
Foreign Exchange Contract [Member] \| Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		0
Derivative Liability, Fair Value, Gross Liability		132
Foreign Exchange Contract [Member] \| Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	9	0
Derivative Liability, Fair Value, Gross Liability	35	$ 0
Derivative Asset	8
Derivative Liability	$ 36

Amount of obligation to return cash collateral under master netting arrangements offset against derivative assets.

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-Publisher FASB
-Name Accounting Standards Codification
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