Derivative Instruments (Balance Sheet Disclosure) (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 1,818	$ 1,971
Derivative Liability	1,370	1,428
Current derivative assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	572	712
Derivative Asset, Collateral, Obligation to Return Cash, Offset	164	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	1,246	1,202
Derivative Asset, Collateral, Obligation to Return Cash, Offset	167	151
Current derivative liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	457	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	913	530
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	17	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	5,116	5,908
Derivative Liability, Fair Value, Gross Liability	4,354	4,740
Derivative Asset	1,818
Derivative Liability	1,370
FPL [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	48	4
Derivative Liability	9	222
FPL [Member] \| Current derivative assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	24	3
FPL [Member] \| Non Current Derivative Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	24	1
FPL [Member] \| Current derivative liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	9	222
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		1,937
Derivative Liability		982
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	5,042	5,906
Derivative Liability, Fair Value, Gross Liability	3,548	4,580
Derivative Asset	1,753
Derivative Liability	573
Commodity Contract [Member] \| FPL [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		4
Derivative Liability		222
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	67	7
Derivative Liability, Fair Value, Gross Liability	28	225
Derivative Asset	48
Derivative Liability	9
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	74	2
Derivative Liability, Fair Value, Gross Liability	761	160
Derivative Asset	65
Derivative Liability	755
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	0	0
Derivative Liability, Fair Value, Gross Liability	45	$ 0
Derivative Asset	0
Derivative Liability	$ 42

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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