Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale debt securities.

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-Publisher FASB

-Name Accounting Standards Codification

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This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

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The cash inflow associated with the sale or maturity (principal being due) of securities not classified as either held-to-maturity securities or trading securities which are classified as available-for-sale securities.

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Fair Value Measurements (Available for Sale Securities) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Realized Gains	$ 35	$ 34	$ 126	$ 182
Realized Losses	21	19	53	99
Proceeds from Sale and Maturity of Available-for-sale Securities	712	879	3,642	3,093
Unrealized losses on available for sale debt securities			40		$ 7
Fair value of available for sale securities in an unrealized loss position	661		661		542
FPL [Member]
Schedule of Available-for-sale Securities [Line Items]
Realized Gains	11	19	56	107
Realized Losses	11	16	26	85
Proceeds from Sale and Maturity of Available-for-sale Securities	556	$ 731	3,094	$ 2,530
Unrealized losses on available for sale debt securities			34		5
Fair value of available for sale securities in an unrealized loss position	$ 516		516		434
Available For Sale Securities: Special Use Funds - Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized gains			1,073		1,267
Available For Sale Securities: Special Use Funds - Equity Securities [Member] \| FPL [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized gains			786		896
available for sale securities: Special Use Funds - Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized gains			26		66
available for sale securities: Special Use Funds - Debt Securities [Member] \| FPL [Member]
Schedule of Available-for-sale Securities [Line Items]
Unrealized gains			$ 21		$ 54