marketable securities, unrealized gain (loss) recognized during the period on securities still held

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- Definition

Storm fund assets held by a regulated entity to pay for storm-related costs as incurred in future periods.

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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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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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No definition available.

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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Amount of cash inflow from sale of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair Value Measurements (Available for Sale Securities) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Marketable Securities, Available-for-sale [Line Items]
Special Use Funds Storm Fund Assets	$ 69		$ 68
Debt Securities [Member]
Marketable Securities, Available-for-sale [Line Items]
Realized Gains	9
Realized Losses	9
Proceeds from sale or maturity of securities	687
debt and equity securities [Member]
Marketable Securities, Available-for-sale [Line Items]
Realized Gains		$ 8
Realized Losses		14
Proceeds from sale or maturity of securities		595
Available for sale securities: Special Use Funds - Debt Securities [Member]
Marketable Securities, Available-for-sale [Line Items]
Unrealized gains	37	14
Available-for-sale Securities, Gross Unrealized Loss	18	52
Fair value of available for sale securities in an unrealized loss position	676		1,273
FPL [Member]
Marketable Securities, Available-for-sale [Line Items]
Special Use Funds Storm Fund Assets	69		68
FPL [Member] \| Debt Securities [Member]
Marketable Securities, Available-for-sale [Line Items]
Realized Gains	5
Realized Losses	4
Proceeds from sale or maturity of securities	543
FPL [Member] \| debt and equity securities [Member]
Marketable Securities, Available-for-sale [Line Items]
Realized Gains		5
Realized Losses		9
Proceeds from sale or maturity of securities		389
FPL [Member] \| Available for sale securities: Special Use Funds - Debt Securities [Member]
Marketable Securities, Available-for-sale [Line Items]
Unrealized gains	28	11
Available-for-sale Securities, Gross Unrealized Loss	14	41
Fair value of available for sale securities in an unrealized loss position	508		$ 961
Equity Securities [Member]
Marketable Securities, Available-for-sale [Line Items]
marketable securities, unrealized gain (loss) recognized during the period on securities still held	367	$ (20)
Equity Securities [Member] \| FPL [Member]
Marketable Securities, Available-for-sale [Line Items]
marketable securities, unrealized gain (loss) recognized during the period on securities still held	$ 234