net unrealized after-tax gains reclassified from AOCI to retained earnings

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27290-111563

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27357-111563

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The total amount of proceeds received for the sale of securities, categorized neither as held-to-maturity nor trading securities, during the reporting period.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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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	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jan. 01, 2018
Schedule of Available-for-sale Securities[Line Items]
Realized gains	$ 178	$ 116	$ 194
Realized losses	83	76	87
Proceeds from sale and maturity of Available-for-sale Securities	2,817	3,400	4,643
Available For Sale Securities: Special Use Funds - Equity Securities [Member]
Schedule of Available-for-sale Securities[Line Items]
Unrealized gains	1,813	1,396
Available for sale securities: Special Use Funds - Debt Securities [Member]
Schedule of Available-for-sale Securities[Line Items]
Unrealized gains	37	22
Unrealized losses	12	34
Fair Value	918	959
FPL[Member]
Schedule of Available-for-sale Securities[Line Items]
Realized gains	75	53	70
Realized losses	50	44	43
Proceeds from sale and maturity of Available-for-sale Securities	1,902	2,442	$ 3,724
FPL[Member] \| Available For Sale Securities: Special Use Funds - Equity Securities [Member]
Schedule of Available-for-sale Securities[Line Items]
Unrealized gains	1,273	1,007
FPL[Member] \| Available for sale securities: Special Use Funds - Debt Securities [Member]
Schedule of Available-for-sale Securities[Line Items]
Unrealized gains	28	17
Unrealized losses	9	28
Fair Value	$ 670	$ 722
Subsequent Event [Member] \| Accounting Standards Update 2016-01 [Member]
Schedule of Available-for-sale Securities[Line Items]
Reclassification of unrealized gains on investments				$ (315)